undici vulnerable to cross-user information disclosure via whitespace around equals in Cache-Control directives

MITRE NVD CVE.ORG JSON API

Summary

CVECVE-2026-14643
StatePUBLISHED
Assigneropenjs
Source PriorityCVE Program / NVD first with legacy fallback
Published2026-07-29 22:16:52 UTC
Updated2026-08-04 15:53:30 UTC
Descriptionundici's cache interceptor mishandles optional whitespace placed around the equals sign of a qualified no-cache or private Cache-Control directive. In undici from 7.0.0 up to before 7.29.0 and from 8.0.0 up to before 8.9.0, the parser either drops the directive or stores a field name with literal quote characters, so the cache decision fails to recognize the qualification and the response is stored. In shared-cache mode, this lets a response containing one user's authenticated data be served from cache to a later caller, including an unauthenticated one, when both requests resolve to the same cache key. It affects applications that enable the cache interceptor in shared mode, forward Authorization headers upstream, and receive cacheable responses with qualified directives padded with whitespace around the equals sign. This is the whitespace-around-equals variant that the fix for CVE-2026-9678 did not normalize, and it is fixed in undici 7.29.0 and 8.9.0.

Risk And Classification

Primary CVSS: v3.1 7.5 HIGH from [email protected]

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

EPSS: 0.002290000 probability, percentile 0.138330000 (date 2026-08-03)

Problem Types: CWE-436 | CWE-524 | CWE-436 CWE-436: Interpretation Conflict | CWE-524 CWE-524: Use of Cache Containing Sensitive Information

VersionSourceTypeScoreSeverityVector
3.1[email protected]Primary7.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
3.1ce714d77-add3-4f53-aff5-83d477b104bbSecondary5.9MEDIUMCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
3.1CNACVSS5.9MEDIUMCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N

CVSS v3.1 Breakdown

Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
None
Availability
None

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

NVD Known Affected Configurations (CPE 2.3)

TypeVendorProductVersionUpdateEditionLanguage
Application Nodejs Undici All All All All

Vendor Declared Affected Products

SourceVendorProductVersionPlatforms
CNA Undici Undici affected 7.0.0 7.29.0 semver Not specified
CNA Undici Undici unaffected 7.29.0 semver Not specified
CNA Undici Undici affected 8.0.0 8.9.0 semver Not specified
CNA Undici Undici unaffected 8.9.0 semver Not specified

References

ReferenceSourceLinkTags
cna.openjsf.org/security-advisories.html ce714d77-add3-4f53-aff5-83d477b104bb cna.openjsf.org Third Party Advisory
github.com/nodejs/undici/security/advisories/GHSA-jr45-8vmc-qm54 ce714d77-add3-4f53-aff5-83d477b104bb github.com Mitigation, Vendor Advisory
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis

Vendor Comments And Credit

Discovery Credit

CNA: rampage0010 (en)

CNA: mcollina (en)

CNA: UlisesGascon (en)

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