缓冲区溢出（buffer overflow）为什么危险？有哪些缓解技术？
Why is a buffer overflow dangerous, and what mitigation techniques exist?
缓冲区溢出指程序向固定大小缓冲区写入超出其容量的数据，覆盖相邻内存，攻击者可借此篡改返回地址并执行任意代码，是早期多数蠕虫的根源。缓解手段包括地址空间布局随机化（ASLR）、数据执行保护（DEP/NX，使栈不可执行）与栈金丝雀（stack canary）等。这些技术由 NIST 与 CERT/CC 等机构长期推广。
A buffer overflow writes more data into a fixed-size buffer than it can hold, overwriting adjacent memory; attackers exploit this to hijack the return address and run arbitrary code, a root cause of many early worms. Mitigations include Address Space Layout Randomization (ASLR), Data Execution Prevention (DEP/NX, making the stack non-executable), and stack canaries. These techniques are long promoted by bodies such as NIST and CERT/CC.
难度 专业 · 适合 高中(15-18)
CC BY 4.0 · 来源待核验 · Source pending review
来源 · Source
出处备注：著录含书名，但缺版次 / 出版社 / 年份中的一部分，需编辑补全后才能做独立比对。
MITRE CWE-120（经典缓冲区溢出）；Aleph One 1996《Smashing the Stack for Fun and Profit》（Phrack 49）；NIST SP 800-53 Rev. 5 控制项 SI-16（内存保护）
MITRE CWE-120 (classic buffer overflow); Aleph One (1996), 'Smashing the Stack for Fun and Profit', Phrack 49; NIST SP 800-53 Rev. 5, control SI-16 (memory protection)
#缓冲区溢出 #ASLR #DEP #CERT
AES 为什么能成为各国政府和企业广泛采用的对称加密标准？
Why did AES become the widely adopted symmetric encryption standard for governments and industry?
AES 是 NIST 在 2001 年通过公开竞赛选出的分组密码，以 Rijndael 算法为基础，支持 128/192/256 位密钥，既安全又适合硬件和软件高效实现。它取代了早期的 DES，成为数据加密的主流。
AES is the block cipher NIST chose through an open competition in 2001, based on the Rijndael algorithm, with 128/192/256-bit keys and efficient hardware and software implementations. It replaced the older DES as the mainstream data-encryption standard.
难度 专业 · 适合 高中(15-18)
CC BY 4.0 · 来源待核验 · Source pending review
来源 · Source
出处备注：著录含书名，但缺版次 / 出版社 / 年份中的一部分，需编辑补全后才能做独立比对。
Daemen 与 Rijmen《AES 提案 Rijndael》(1999)；美国 NIST《高级加密标准》(FIPS 197, 2001)
Daemen & Rijmen, 'The Rijndael Block Cipher' (AES proposal, 1999); US NIST, 'Advanced Encryption Standard' (FIPS 197, 2001)
#AES #对称加密 #分组密码 #NIST
OAuth 2.0 的授权码模式为什么比把密码直接交给第三方应用更安全？
Why is the OAuth 2.0 authorization-code flow safer than handing passwords directly to third-party apps?
授权码模式下，第三方应用先把用户引导到授权服务器登录，用户授权后拿到的是"授权码"而不是令牌，并且令牌由第三方应用在后端用 client secret 换取，全程不经过浏览器。这样用户的密码不会泄露给第三方，令牌也减少了在浏览器中被截获的机会，还支持作用域限制和刷新令牌。
In the authorization-code flow, the third-party app redirects the user to the authorization server; after consent it receives an authorization code — not a token — and exchanges it for a token in the backend using its client secret, never through the browser. The user's password is never exposed to the third party, the risk of token interception in the browser drops, and scopes plus refresh tokens add further control.
难度 专业 · 适合 高中(15-18)
CC BY 4.0 · 已核验 · Verified 2026-11-04 · 2 条独立证据
来源 · Source
Hardt,《The OAuth 2.0 Authorization Framework》,2012 (DOI: 10.17487/rfc6749)
Hardt, 'The OAuth 2.0 Authorization Framework', 2012, DOI: 10.17487/rfc6749
独立核验依据 · Independent verification: 核验依据 1 Crossref DOI 10.17487/rfc6749 · 核验依据 2 ARCHIVE 标识 rfc6749：The OAuth 2.0 Authorization Framework
#OAuth #授权码 #身份认证
最小权限原则（principle of least privilege）是什么？
What is the principle of least privilege?
最小权限原则要求每个程序与用户只拥有完成其任务所必需的最低权限，既不多也不少，从而限制一旦被攻破时的破坏范围。它由萨尔泽与施罗德在 1975 年的经典论文中系统提出，并被 NIST 采纳为安全设计的基本要求。它是纵深防御与权限隔离的理论基石。
The principle of least privilege requires that every program and user be given only the minimum permissions needed to perform its task, no more, limiting the blast radius if compromised. Systematized by Saltzer and Schroeder in their 1975 classic paper, it is adopted by NIST as a basic security-design requirement. It is the theoretical cornerstone of defense in depth and privilege separation.
难度 专业 · 适合 高中(15-18)
CC BY 4.0 · 已核验 · Verified 2026-11-04
来源 · Source
Saltzer & Schroeder 1975《The Protection of Information in Computer Systems》（Proceedings of the IEEE 63(9)）；NIST SP 800-53 Rev. 5 控制项 AC-6（最小权限）
Saltzer & Schroeder (1975), 'The Protection of Information in Computer Systems', Proceedings of the IEEE 63(9); NIST SP 800-53 Rev. 5, control AC-6 (least privilege)
独立核验依据 · Independent verification: 核验依据 1 Crossref DOI 10.1109/proc.1975.9939（复合著录按段核验：本标识只担保『Salt
#最小权限 #萨尔泽 #安全设计 #NIST
Diffie-Hellman 密钥交换是怎样让双方在不安全信道上共享秘密的？
How does Diffie-Hellman key exchange let two parties share a secret over an insecure channel?
双方各自选私密指数，公开交换各自计算的幂值；由于离散对数难反解，窃听者拿不到中间结果也无法算出共同的共享密钥。Diffie 与 Hellman 在 1976 年发表，开启了无预先秘密也能协商密钥的可能。
Each side picks a secret exponent and publicly exchanges computed powers; because the discrete logarithm is hard to invert, an eavesdropper cannot derive the shared secret from what is visible. Diffie and Hellman published it in 1976, enabling key agreement without prior secrets.
难度 专业 · 适合 高中(15-18)
CC BY 4.0 · 来源待核验 · Source pending review
来源 · Source
出处备注：著录含书名，但缺版次 / 出版社 / 年份中的一部分，需编辑补全后才能做独立比对。
Diffie 与 Hellman《密码学的新方向》(IEEE Trans Inf Theory, 1976)；美国 NIST《密钥管理建议》
Diffie & Hellman, 'New Directions in Cryptography' (1976); US NIST, 'Key Management Guidelines'
#Diffie-Hellman #离散对数 #密钥协商 #公开参数
跨站脚本（XSS）攻击是怎么发生的？
How does a cross-site scripting (XSS) attack work?
当网站把用户输入直接插进网页而不过滤时，攻击者提交的 <script> 代码会作为页面的一部分被其他用户的浏览器执行。这样能偷走别人的登录 Cookie、伪造表单或劫持会话。防御在于“输出编码”：把用户内容当纯文本渲染而非可执行代码，并配合 CSP（内容安全策略）限制脚本来源。
When a site inserts user input into pages without sanitizing it, <script> code submitted by an attacker executes in other users' browsers as part of the page. That lets attackers steal login cookies, forge forms, or hijack sessions. Defense is output encoding—rendering user content as inert text, not executable code—plus CSP (Content Security Policy) to restrict where scripts may come from.
难度 专业 · 适合 高中(15-18)
CC BY 4.0 · 来源待核验 · Source pending review
来源 · Source
出处备注：著录仅给书名，无版次与年份；同一书名常对应多个版次，不臆测具体版本。
OWASP《十大 Web 应用安全风险》(Top 10)；MITRE《CWE-89 SQL 注入》
OWASP, 'Top 10 Web Application Security Risks'; MITRE, 'CWE-89: SQL Injection'
#XSS #跨站脚本 #输出编码
TLS 是怎么在公开网络上保证通信既加密又不被篡改的？
How does TLS keep communication over public networks both encrypted and un-tampered?
TLS 先用非对称密码（如 RSA 或 Diffie-Hellman）完成身份认证并协商出对称会话密钥，之后用该密钥对流量加密并用消息认证码(MAC)检测篡改。握手还依赖可信证书链来验证对方身份。
TLS first uses asymmetric crypto (RSA or Diffie-Hellman) to authenticate and negotiate a symmetric session key, then encrypts traffic with it and uses a MAC to detect tampering. The handshake also relies on trusted certificate chains to verify identity.
难度 专业 · 适合 高中(15-18)
CC BY 4.0 · 来源待核验 · Source pending review
来源 · Source
出处备注：著录含书名，但缺版次 / 出版社 / 年份中的一部分，需编辑补全后才能做独立比对。
IETF《TLS 1.2》(RFC 5246, 2008)；IETF《TLS 1.3》(RFC 8446, 2018)
IETF, 'TLS 1.2' (RFC 5246, 2008); IETF, 'TLS 1.3' (RFC 8446, 2018)
#TLS #握手 #证书链 #消息认证码
RSA 公钥加密的安全性建立在什么数学难题上？
On what mathematical problem does RSA public-key encryption rely for security?
RSA 用一对公私钥，加密基于『大整数分解困难』：把两个大素数相乘很容易，但要从乘积反推这两个素数在经典计算机上极难。Rivest、Shamir 与 Adleman 在 1978 年提出，是现代公钥密码的奠基之一。
RSA uses a public/private key pair whose security rests on the hardness of factoring: multiplying two large primes is easy, but recovering them from the product is intractable classically. Rivest, Shamir, and Adleman proposed it in 1978, founding public-key cryptography.
难度 专业 · 适合 高中(15-18)
CC BY 4.0 · 来源待核验 · Source pending review
来源 · Source
出处备注：著录含书名，但缺版次 / 出版社 / 年份中的一部分，需编辑补全后才能做独立比对。
Rivest、Shamir 与 Adleman《公钥密码学》(CACM, 1978)；美国 NIST《数字签名标准》
Rivest, Shamir & Adleman, 'A Method for Obtaining Digital Signatures' (CACM, 1978); US NIST, 'Digital Signature Standard'
#RSA #大整数分解 #公钥 #私钥
什么是服务端请求伪造（SSRF）？为什么云环境中的攻击者格外关注链路本地地址 169.254.169.254 这样的实例元数据端点？列出几类有效的防御措施。
What is server-side request forgery (SSRF)? Why do attackers in cloud environments pay special attention to instance metadata endpoints such as the link-local address 169.254.169.254? List several effective defenses.
应用若不加限制地按用户提供的 URL 发起请求，攻击者便可驱使服务器访问其内网中本不该暴露的服务，这就是 SSRF。云实例的元数据端点绑定在链路本地地址上，仅实例内部可达，返回临时访问凭证等机密，被读取后攻击者即可冒充该实例提权。防御包括：域名白名单并在 DNS 解析后拒绝私网与链路本地 IP、禁止自动跟随重定向、为元数据服务启用须携带令牌头的会话（IMDSv2）、收紧出站网络策略。
When an application issues requests to URLs supplied by users without constraints, attackers can steer the server toward services in its own network that were never meant to be exposed; that is SSRF. A cloud instance's metadata endpoint binds to a link-local address reachable only from the instance itself, and it hands out secrets such as temporary access credentials, whose theft lets an attacker impersonate the instance. Defenses include domain allowlists with rejection of private and link-local IPs after DNS resolution, refusing automatic redirects, token-header sessions for metadata such as IMDSv2, and tightened outbound policy.
难度 专业 · 适合 高中(15-18)
CC BY 4.0 · 来源待核验 · Source pending review
来源 · Source
出处备注：此条未指向带版次的可引用著作（通识性内容、机构文件或未展开的英文书名），本库不提供独立书目出处；如需精确引用，需由编辑补全具体篇目与版次。
Orange Tsai 议题演讲 SSRF 新纪元：利用主流编程语言的 URL 解析器，Black Hat USA 2017
O. Tsai, A New Era of SSRF: Exploiting URL Parser in Trending Programming Languages, Black Hat USA 2017
#Web安全 #SSRF #云元数据
经典的缓冲区溢出攻击是怎么发生的？现代系统如何防御？
How does the classic buffer-overflow attack work, and how do modern systems defend against it?
如果程序向固定大小的栈缓冲区写入超长数据且不做边界检查，溢出数据会覆盖相邻的返回地址；攻击者把精心构造的地址与 shellcode 布局好，函数返回时 CPU 就跳到恶意代码执行。现代防御包括栈金丝雀（canary）、NX（禁止栈上执行）、ASLR 地址空间随机化、编译器加固选项，以及改用内存安全的语言。
If a program writes past the end of a fixed-size stack buffer without bounds checking, the overflow overwrites the adjacent return address; attackers lay out a crafted address and shellcode, and when the function returns the CPU jumps to the malicious code. Modern defenses include stack canaries, NX (no-execute stacks), ASLR address-space randomization, compiler hardening flags, and moving to memory-safe languages.
难度 专业 · 适合 高中(15-18)
CC BY 4.0 · 来源待核验 · Source pending review
来源 · Source
出处备注：本题原挂出处与答案内容不符，已撤回；具体书目待补，暂不展示来源。
本题原挂出处与答案内容不符，已撤回；具体书目待补。
Previous citation withdrawn as unsupported for this answer; a specific source is pending.
#缓冲区溢出 #栈溢出 #内存安全
零知识证明让一方『证明知道某秘密』却不泄露秘密，这可能吗？
Can one party prove it knows a secret without revealing it—is zero-knowledge proof real?
零知识证明通过交互式挑战，让证明者以极高概率使验证者信服自己掌握某信息（如离散对数），却不让对方学到任何可用片段。Goldwasser、Micali 与 Rackoff 在 1985 年提出这一概念，如今用于隐私币和身份认证。
A zero-knowledge proof uses interactive challenges so the prover convinces the verifier it knows something (e.g., a discrete log) with overwhelming probability while revealing no usable information. Goldwasser, Micali, and Rackoff introduced it in 1985; it now underpins privacy coins and authentication.
难度 专业 · 适合 高中(15-18)
CC BY 4.0 · 已核验 · Verified 2026-11-03
来源 · Source
Goldwasser、Micali 与 Rackoff《交互式证明系统的知识复杂度》(SIAM Journal on Computing, 1985)；Katz 与 Lindell《现代密码学引论》
Goldwasser, Micali & Rackoff, 'The Knowledge Complexity of Interactive Proof Systems' (SIAM Journal on Computing, 1985); Katz & Lindell, 'Introduction to Modern Cryptography'
独立核验依据 · Independent verification: 核验依据 1 OPENLIBRARY 标识 /works/OL508869W：Introduction to modern c
#零知识证明 #交互式 #验证者 #隐私
为什么区块链难以篡改？
Why is blockchain hard to tamper?
每个区块头里写着前一个区块的哈希，改动任何一条历史交易都会让那一块的哈希变化，进而让它之后的所有块都指向错误的地址，整条链当场断裂。要真正改掉，攻击者必须把目标块之后的每个块都重新算一遍，并且算得比全网其余人更快，才能让自己的版本成为「最长链」被接受——在工作量证明下这就是拼算力，也就是常说的「过半算力」问题。再加上历史记录早已复制在成千上万台独立节点上，改自己那份没有意义。难篡改不是数学上的不可能，而是成本高于收益。
Every block header carries the hash of the block before it, so changing any past transaction changes that block's hash, which makes every later block point at the wrong address and the chain breaks. To really alter history an attacker must recompute every block after the target one and do it faster than the rest of the network combined, so that his version becomes the accepted longest chain - under proof of work that is a hash-rate contest, which is what the 'majority of hash power' phrase is about. On top of that, the history is already duplicated across thousands of independent nodes, so editing your own copy means nothing. Tamper-resistance is not mathematical impossibility; it is that the cost exceeds the payoff.
难度 专业 · 适合 高中(15-18)
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
Ferguson、Schneier、Kohno,《Cryptography Engineering》Wiley,2010
N. Ferguson, B. Schneier and T. Kohno, Cryptography Engineering, Wiley, 2010
独立核验依据 · Independent verification: 核验依据 2 OPENLIBRARY 标识 /works/OL16596906W：Cryptography engineeri
#哈希 #链式 #共识
SQL 注入攻击是怎么回事，为什么参数化查询能防住它？
What is a SQL injection attack, and why does parameterized querying prevent it?
攻击者把恶意 SQL 片段拼进用户输入，使数据库误把其当作指令执行，从而窃取或破坏数据。参数化查询把代码与数据分开，转义并绑定变量，让输入永远只当数据、不当命令。OWASP 将其列为头号 Web 风险之一。
An attacker concatenates malicious SQL into user input so the database mistakes it for commands, stealing or wrecking data. Parameterized queries separate code from data by binding variables, so input is always treated as data, never as a command. OWASP lists it among top web risks.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 来源待核验 · Source pending review
来源 · Source
出处备注：著录仅给书名，无版次与年份；同一书名常对应多个版次，不臆测具体版本。
OWASP《十大 Web 应用安全风险》(Top 10)；MITRE《CWE-89 SQL 注入》
OWASP, 'Top 10 Web Application Security Risks'; MITRE, 'CWE-89: SQL Injection'
#SQL注入 #参数化查询 #输入验证 #OWASP
浏览器与网站建立 HTTPS 连接时，TLS 握手大致做了什么？
Roughly what happens during the TLS handshake when a browser opens an HTTPS site?
TLS 握手在传输业务数据前完成三件事：协商密码套件（协议版本与加密算法）、用服务器证书验证服务器身份、通过密钥交换（如 ECDHE）在不暴露密钥的前提下生成共享的会话密钥。此后双方用对称密钥加密通信，保证机密性、完整性并具备身份认证。
Before any application data, the TLS handshake does three things: negotiate the cipher suite (protocol version and encryption algorithms), verify the server's identity using its certificate, and establish a shared session key via key exchange such as ECDHE without exposing the key. Both sides then encrypt traffic with symmetric keys, providing confidentiality, integrity and authentication.
难度 进阶 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-11-02
来源 · Source
《计算机网络》第7章
Computer Networking (《计算机网络》), ch. 7
独立核验依据 · Independent verification: 核验依据 1 ISBN 9787121411748（豆瓣书目条目: 计算机网络）
#TLS #HTTPS #握手
数字签名怎么同时保证"内容没被改"和"确实是你签的"？
How does a digital signature prove both integrity and authenticity at the same time?
签名方对消息做哈希得到摘要，再用自己的私钥加密摘要形成签名；验证方用公钥解开签名恢复摘要，与对收到的消息重新计算的哈希比对。由于私钥只有签名者持有，能通过验证的签名必然出自持钥者；消息一旦被改动哈希就对不上，因此签名同时提供了完整性与不可抵赖性。
The signer hashes the message and encrypts the digest with their private key; the verifier decrypts the digest with the public key and compares it with a freshly computed hash of the received message. Because only the signer holds the private key, any signature that verifies must come from them, and any modification breaks the hash match — so signatures provide both integrity and non-repudiation.
难度 进阶 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-11-02
来源 · Source
《计算机网络》第7章
Computer Networking (《计算机网络》), ch. 7
独立核验依据 · Independent verification: 核验依据 1 ISBN 9787121411748（豆瓣书目条目: 计算机网络）
#数字签名 #公钥密码 #哈希
什么是软件供应链攻击？为什么"用开源库"也带来风险？
What is a software supply-chain attack, and why does using open-source libraries carry risk?
现代软件大量复用第三方组件，供应链攻击指攻击者通过污染依赖库、构建工具或更新通道，把恶意代码带入受害者系统，例如 2021 年的 SolarWinds 事件和 2024 年的 XZ utils 后门。防御手段包括依赖锁定与校验、软件物料清单（SBOM）、代码签名和持续漏洞扫描。
Modern software heavily reuses third-party components; a supply-chain attack compromises dependencies, build tools or update channels to smuggle malicious code into victims' systems — for example SolarWinds in 2021 and the XZ utils backdoor in 2024. Defenses include dependency locking and verification, software bills of materials (SBOM), code signing, and continuous vulnerability scanning.
难度 进阶 · 适合 大众
CC BY 4.0 · 来源待核验 · Source pending review
来源 · Source
出处备注：此条未指向带版次的可引用著作（通识性内容、机构文件或未展开的英文书名），本库不提供独立书目出处；如需精确引用，需由编辑补全具体篇目与版次。
DIMVA（Ohm 等, Backstabber's Knife Collection: 开源软件供应链攻击综述, 2020）
DIMVA (Ohm et al., Backstabber's Knife Collection: A Review of Open Source Software Supply Chain Attacks, 2020)
#供应链安全 #依赖 #SBOM
App 为什么收集那么多数据？“隐私”在技术层面指什么？
Why do apps collect so much data, and what does privacy mean technically?
位置、行为、通讯录等数据让产品可以做个性化推荐、广告定向和功能优化，所以商业上被极力收集。技术层面保护隐私的手段包括数据最小化（只用必要数据）、匿名化、去标识化（去掉能认出你的字段）和加密；其中去标识化并不绝对安全，结合多份数据仍可能重新识别出个人，这正是隐私研究的难点。
Location, behavior, contacts, and more enable personalized recommendations, targeted ads, and product optimization, so there is commercial pressure to collect aggressively. Technical privacy safeguards include data minimization (only what's needed), anonymization, de-identification (stripping identifying fields), and encryption; de-identification is not foolproof, because combining datasets can still re-identify individuals—the crux of privacy research.
难度 进阶 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-11-04
来源 · Source
Dwork 与 Roth,《The Algorithmic Foundations of Differential Privacy》,Foundations and Trends® in Theoretical Computer Science,2014 (DOI: 10.1561/0400000042)
Dwork, C. & Roth, A., 'The Algorithmic Foundations of Differential Privacy', Foundations and Trends® in Theoretical Computer Science, 2014, DOI: 10.1561/0400000042
独立核验依据 · Independent verification: 核验依据 1 Crossref DOI 10.1561/0400000042
#隐私 #数据最小化 #匿名化
多因素认证（MFA）为什么更安全？
Why is multi-factor authentication more secure?
MFA 要求同时提供两种以上独立凭证（密码、手机验证码、生物特征），即使密码泄露，攻击者仍缺少第二因素，难以登录。
MFA requires two or more independent factors (password, phone code, biometrics); even if the password leaks, the attacker lacks the second factor and cannot log in.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-11-06
来源 · Source
NIST SP 800-63B
NIST SP 800-63B
独立核验依据 · Independent verification: 核验依据 1 NIST SP 800-63B · DOI 10.6028/NIST.SP.800-63b
#安全 #认证
为什么病毒会感染电脑？
Why do computer viruses infect?
恶意程序借文件或漏洞复制自身并破坏系统。
Malware copies itself via files or flaws and harms systems.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
Ferguson、Schneier、Kohno,《Cryptography Engineering》Wiley,2010
N. Ferguson, B. Schneier and T. Kohno, Cryptography Engineering, Wiley, 2010
独立核验依据 · Independent verification: 核验依据 2 OPENLIBRARY 标识 /works/OL16596906W：Cryptography engineeri
#恶意软件 #漏洞 #复制
密码学哈希函数为什么要求『抗原像』和『抗碰撞』？
Why must a cryptographic hash function be preimage-resistant and collision-resistant?
哈希把任意长度输入压成固定长度摘要，抗原像指无法从摘要反推原文，抗碰撞指难以找到两个不同输入产生同一摘要。这两者保证了数字签名、口令存储和完整性校验的安全基础（如 SHA 系列由 NIST 标准化）。
A hash compresses arbitrary input to a fixed digest; preimage resistance means you cannot invert the digest, and collision resistance means finding two inputs with the same digest is infeasible. Together they secure digital signatures, password storage, and integrity checks (e.g., the SHA family standardized by NIST).
难度 进阶 · 适合 高中(15-18)
CC BY 4.0 · 已核验 · Verified 2026-11-03
来源 · Source
美国 NIST《安全哈希标准》(FIPS 180)；Rivest《MD5》(1992)
US NIST, 'Secure Hash Standard' (FIPS 180); Rivest, 'The MD5 Message-Digest Algorithm' (1992)
独立核验依据 · Independent verification: 核验依据 1 ARCHIVE 标识 bitsavers_fipsFIPS18d_214998：fips :: FIPS 180
#哈希函数 #抗原像 #抗碰撞 #SHA
什么是中间人攻击？
What is a man-in-the-middle attack?
中间人攻击是攻击者暗中截获并可能篡改通信双方的数据，常见手段有伪造证书、ARP 欺骗；使用 HTTPS、证书固定和 VPN 可削弱此类风险。
A MITM attack secretly intercepts and possibly alters traffic between two parties, e.g. via forged certificates or ARP spoofing; HTTPS, certificate pinning and VPNs mitigate it.
难度 进阶 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
Ferguson、Schneier、Kohno,《Cryptography Engineering》Wiley,2010
N. Ferguson, B. Schneier and T. Kohno, Cryptography Engineering, Wiley, 2010
独立核验依据 · Independent verification: 核验依据 2 OPENLIBRARY 标识 /works/OL16596906W：Cryptography engineeri
#安全 #攻击
同态加密能做什么特别的事？
What special thing can homomorphic encryption do?
同态加密允许在密文上直接计算，得到的结果解密后等于对明文计算的结果，因此可在不看到数据内容的前提下帮他人做运算，适用于隐私保护的云端计算。
Homomorphic encryption lets you compute directly on ciphertext so the decrypted result equals computing on plaintext, enabling privacy-preserving cloud computation without seeing the data.
难度 进阶 · 适合 大众
CC BY 4.0 · 来源待核验 · Source pending review
来源 · Source
出处备注：此条未指向带版次的可引用著作（通识性内容、机构文件或未展开的英文书名），本库不提供独立书目出处；如需精确引用，需由编辑补全具体篇目与版次。
Gentry 2009
Gentry 2009
#密码学 #隐私
跨站脚本攻击（XSS）是什么？如何防御？
What is cross-site scripting (XSS), and how is it defended against?
XSS 是攻击者把恶意脚本注入到其他用户浏览的网页中、在其浏览器里执行的攻击，常用于盗取会话或钓鱼。防御核心是输出编码（按 HTML/JS 上下文转义）与内容安全策略（CSP），并对用户输入做严格校验。它位列 OWASP 十大风险，在 MITRE CWE 中编号为 CWE-79。
XSS is an attack where the attacker injects malicious scripts into web pages viewed by other users, executing in their browsers to steal sessions or phish. Defense centers on output encoding (escaping per HTML/JS context) and Content Security Policy (CSP), plus strict input validation. It appears in the OWASP Top 10 and is cataloged as CWE-79 by MITRE.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 来源待核验 · Source pending review
来源 · Source
出处备注：此条未指向带版次的可引用著作（通识性内容、机构文件或未展开的英文书名），本库不提供独立书目出处；如需精确引用，需由编辑补全具体篇目与版次。
OWASP Top 10；MITRE CWE-79
OWASP Top 10; MITRE CWE-79
#XSS #跨站脚本 #内容安全策略 #OWASP
双因素认证（2FA）为什么比单纯密码更安全？"因素"指什么？
Why is two-factor authentication (2FA) safer than a password alone? What counts as a "factor"?
认证因素分三类：所知（密码、PIN）、所有（手机验证码、TOTP、硬件钥匙）、所是（指纹、人脸）。2FA 要求同时出示两个不同类别的因素，攻击者即使窃取了密码，缺少第二个因素也无法登录，从而显著降低撞库和钓鱼造成的风险。
Authentication factors fall into three types: something you know (password, PIN), something you have (SMS code, TOTP, hardware key), and something you are (fingerprint, face). 2FA requires two factors of different types, so even if attackers steal the password they cannot log in without the second factor — sharply reducing the impact of credential stuffing and phishing.
难度 进阶 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-11-06
来源 · Source
美国国家标准与技术研究院（NIST）SP 800-63B
NIST SP 800-63B
独立核验依据 · Independent verification: 核验依据 1 NIST SP 800-63B · DOI 10.6028/NIST.SP.800-63b
#双因素认证 #身份验证 #安全
零信任安全模型的核心假设是什么？
What is the core assumption of zero-trust security?
零信任假设网络内外部都不可信，不再依赖边界防御，而是对每个请求进行身份、设备和上下文的持续验证，并遵循最小权限与微隔离。
Zero trust assumes no implicit trust inside or outside the network; instead of perimeter defense it continuously verifies identity, device and context per request, enforcing least privilege and micro-segmentation.
难度 进阶 · 适合 大众
CC BY 4.0 · 来源待核验 · Source pending review
来源 · Source
出处备注：此条未指向带版次的可引用著作（通识性内容、机构文件或未展开的英文书名），本库不提供独立书目出处；如需精确引用，需由编辑补全具体篇目与版次。
NIST SP 800-207
NIST SP 800-207
#安全 #架构
CSRF 攻击为什么不需要窃取密码，而是利用浏览器自动携带 Cookie 的机制？
Why does CSRF need no stolen password, exploiting instead how browsers attach cookies automatically?
登录后，会话 Cookie 由浏览器自动管理：向该站的请求都会自动附上它。恶意页面诱骗浏览器发出改邮箱、转账等变更请求时，Cookie 照常随行，服务器无从分辨用户本意与伪造——攻击者无需读取任何凭据。防御因此要补上意图证明：绑定会话的防伪令牌、限制跨站的 SameSite Cookie 以及 Origin 校验。
After login, a site's session cookie is managed automatically by the browser: every request toward that site carries it along. When a malicious third-party page tricks the browser into sending a state-changing request - changing an email address, transferring money - the cookie rides along as usual, and the server cannot tell user intent from forgery; the attacker never reads any credential. Defenses add explicit proof of intent: per-session anti-forgery tokens, SameSite cookies restricting cross-site sending, and Origin header checks.
难度 进阶 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-11-04
来源 · Source
A. Barth、C. Jackson 与 J. C. Mitchell,《Robust defenses for cross-site request forgery》,ACM CCS 会议论文集,2008 (DOI: 10.1145/1455770.1455782)
A. Barth, C. Jackson & J. C. Mitchell, 'Robust defenses for cross-site request forgery', Proc. ACM CCS, 2008, DOI: 10.1145/1455770.1455782
独立核验依据 · Independent verification: 核验依据 1 Crossref DOI 10.1145/1455770.1455782
#Web安全 #CSRF #Cookie会话
零信任安全模型和传统的"内网可信"模型有什么不同？
How does the zero-trust security model differ from the traditional "trust the internal network" model?
传统模型假设内网可信、外网可疑，攻击者一旦进入内网就能低成本横向移动。零信任默认"永不信任、始终验证"：无论请求来自内网还是外网，都持续校验身份、设备健康与授权，并授予最小权限。它假设边界早已被攻破，把安全控制从网络层下沉到每个请求和资源。
The traditional model trusts the internal network and suspects the outside, letting attackers move laterally at low cost once inside. Zero trust assumes "never trust, always verify": every request, internal or external, is continuously checked for identity, device health and authorization, with least-privilege access. It assumes the perimeter is already breached and pushes security control down to each request and resource.
难度 进阶 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-11-04
来源 · Source
Елена, Роман,《Сравнительный анализ концепции Zero Trust и традиционной модели информационной безопасности》,Scientific works of KubSTU,2026 (DOI: 10.26297/2312-9409.2025.6.12)
Елена, Роман, 'Сравнительный анализ концепции Zero Trust и традиционной модели информационной безопасности', Scientific works of KubSTU, 2026, DOI: 10.26297/2312-9409.2025.6.12
独立核验依据 · Independent verification: 核验依据 1 Crossref DOI 10.26297/2312-9409.2025.6.12
#零信任 #网络安全 #最小权限
防火墙（firewall）是用来做什么的？
What is a firewall used for?
防火墙是一种根据预设规则监控和过滤进出网络流量的安全设备或软件，像一道门卫挡住未经授权的访问。它可以基于 IP、端口、协议等条件放行或阻断连接，是网络边界防护的第一道屏障。其使用由美国国家标准与技术研究院（NIST）在 SP 800-41 中给出权威指南。
A firewall is a security device or software that monitors and filters incoming and outgoing network traffic according to preset rules, acting like a gatekeeper that blocks unauthorized access. It permits or blocks connections based on criteria such as IP, port, and protocol, forming the first line of network perimeter defense. The NIST SP 800-41 provides authoritative guidance on firewall use.
难度 入门 · 适合 小学低段(6-8)
CC BY 4.0 · 已核验 · Verified 2026-11-04
来源 · Source
NIST SP 800-41 Rev. 1《Guidelines on Firewalls and Firewall Policy》（2009）；IETF RFC 2979（防火墙行为要求）
NIST SP 800-41 Rev. 1, 'Guidelines on Firewalls and Firewall Policy' (2009); IETF RFC 2979 (firewall behavioral requirements)
独立核验依据 · Independent verification: 核验依据 1 Crossref DOI 10.6028/nist.sp.800-41r1
#防火墙 #网络边界 #流量过滤 #NIST
为什么要定期改密码？
Why change passwords regularly?
如果密码曾泄露而你不知道，定期更换能缩短攻击者可用的窗口；更重要的是用长且独特的密码并开启两步验证。
If a password leaked unnoticed, rotating it shrinks the attacker's window; even better is using long unique passwords plus two-step verification.
难度 入门 · 适合 小学低段(6-8)
CC BY 4.0 · 已核验 · Verified 2026-11-06
来源 · Source
NIST SP 800-63B
NIST SP 800-63B
独立核验依据 · Independent verification: 核验依据 1 NIST SP 800-63B · DOI 10.6028/NIST.SP.800-63b
#安全 #密码