GHSA-pr7r-676h-xcf6

    Dashboard / Vulnerabilities / GHSA-pr7r-676h-xcf6

    GHSA-pr7r-676h-xcf6

    Published: 18 Jun 2026Last Modified: 10 Sept 2026
    Aliases:

    Summary: undici vulnerable to cross-user information disclosure via shared cache whitespace bypass

    Details: ## Impact Undici's cache interceptor incorrectly classifies some responses as cacheable when the upstream `Cache-Control` header uses whitespace-padded qualified `private` or `no-cache` field names such as `private=" authorization"` or `no-cache="\tauthorization"`. The parser preserves the surrounding whitespace, so later comparisons against the literal `authorization` field name fail and the response is stored. In shared-cache mode, this allows a response containing one user's authenticated data to be served from cache to a subsequent caller, including an unauthenticated caller, when both requests resolve to the same cache key. Affected applications are those that explicitly enable the cache interceptor (`interceptors.cache()`) in shared mode, forward `Authorization` headers upstream, and receive cacheable responses with non-canonical qualified `private` or `no-cache` directives. ## Patches Upgrade to undici v7.28.0 or v8.5.0. ## Workarounds If upgrade is not immediately possible, disable shared-cache mode for traffic that includes `Authorization` headers, avoid caching responses to authenticated requests, or add `Vary: Authorization` upstream.

    Affected packages

    Package

    Name: undici

    Purl: pkg:npm/undici

    Affected ranges

    Type: SEMVER

    Events:

    Introduced- 7.0.0
    Fixed -7.28.0

    Affected versions

    Common Vulnerability Scoring System

    Attack Vector
    Network
    Adjacent
    Local
    Physical
    Privileges Required
    None
    Low
    High
    User Interaction
    None
    Required
    Scope
    Unchanged
    Changed
    Confidentiality
    None
    Low
    High
    Integrity
    None
    Low
    High
    Availability
    None
    Low
    High
    GHSA-pr7r-676h-xcf6 | CVE-DB