websafe-kb/07-framework-security/frameworks/flask/cases/flask-cve-2026-27205.md

title, system_id, category, advisory_mode, published_date, updated_date, severity, exploit_status, source_confidence, verification_status, verification_mode, artifact_mode, last_run_id, target_types, allow_public_validation, authorization_prerequisite, minimal_validation, aliases, affected_versions, fixed_versions, secure_code_topics, primary_source

title	system_id	category	advisory_mode	published_date	updated_date	severity	exploit_status	source_confidence	verification_status	verification_mode	artifact_mode	last_run_id	target_types	allow_public_validation	authorization_prerequisite	minimal_validation	aliases	affected_versions	fixed_versions	secure_code_topics	primary_source
Flask session does not add `Vary: Cookie` header when accessed in some ways	flask	frameworks	core	2026-02-19T20:45:41Z	2026-02-23T23:43:45.778179Z	medium	unknown	official	triage-manual	synthetic	synthetic		lab-local lab-public authorized-third-party	yes, with ownership or explicit authorization	asset ownership proof or explicit written authorization	read-only probe, controlled payload, reversible test	CVE-2026-27205 GHSA-68rp-wp8r-4726	0.1 0.10 0.10.1 0.11 0.11.1 0.12 0.12.1 0.12.2 0.12.3 0.12.4 0.12.5 0.2 0.3 0.3.1 0.4 0.5 0.5.1 0.5.2 0.6 0.6.1	3.1.3	xss-output-encoding ssrf-url-validation token-cookie-storage proxy-trust-boundary	https://github.com/pallets/flask/security/advisories/GHSA-68rp-wp8r-4726

Flask session does not add Vary: Cookie header when accessed in some ways

本地实证状态

• 实证状态: triage-manual
• 实证方式: synthetic
• Artifact 模式: synthetic
• 最近运行: -
• 浏览器证据: missing
• Run Bundle: -

事件层

• Canonical ID: flask--CVE-2026-27205
• 系统: flask
• 严重度: medium
• 来源置信度: official
• 官方主源: https://github.com/pallets/flask/security/advisories/GHSA-68rp-wp8r-4726
• 影响版本: 0.1, 0.10, 0.10.1, 0.11, 0.11.1, 0.12, 0.12.1, 0.12.2, 0.12.3, 0.12.4
• 修复版本: 3.1.3

其他来源

• https://nvd.nist.gov/vuln/detail/CVE-2026-27205
• 089cb86dd2
• https://github.com/pallets/flask
• https://github.com/pallets/flask/releases/tag/3.1.3

实验层

• 仅用于自有资产、测试环境或已明确授权目标。
• 允许公网可达目标，但必须满足资产归属或明确授权前提。
• 最小化验证方式: 最小化验证、只读探测、可审计回显、受控注入。
• 若该案例涉及插件、模块或扩展，应同时检查供应链与升级策略。
• 禁止场景: 无归属证明或无明确授权的公网目标；知名公共网站或与测试无关的第三方资产；会造成持久破坏、数据越权下载或不可回滚影响的动作

修复示例

• javascript-typescript:xss-output-encoding
• nodejs:xss-output-encoding
• java:xss-output-encoding
• php:xss-output-encoding
• python:xss-output-encoding
• ruby:xss-output-encoding
• csharp:xss-output-encoding
• go:xss-output-encoding
• javascript-typescript:ssrf-url-validation
• nodejs:ssrf-url-validation
• java:ssrf-url-validation
• php:ssrf-url-validation
• python:ssrf-url-validation
• ruby:ssrf-url-validation
• csharp:ssrf-url-validation
• go:ssrf-url-validation
• javascript-typescript:token-cookie-storage
• nodejs:token-cookie-storage
• java:token-cookie-storage
• php:token-cookie-storage
• python:token-cookie-storage
• ruby:token-cookie-storage
• csharp:token-cookie-storage
• go:token-cookie-storage
• javascript-typescript:proxy-trust-boundary
• nodejs:proxy-trust-boundary
• java:proxy-trust-boundary
• php:proxy-trust-boundary
• python:proxy-trust-boundary
• ruby:proxy-trust-boundary
• csharp:proxy-trust-boundary
• go:proxy-trust-boundary