CVE-2026-84933

Aliases:DEBIAN-CVE-2026-84933UBUNTU-CVE-2026-84933CGA-2f38-87jj-mp3jCGA-fvw7-pg64-rqj6
Advisory lineage Upstream: 0 Downstream: 3
Analyzed
Published: 04 Sept 2026, 16:59
Last modified:04 Sept 2026, 18:34

Vulnerability Summary

Overall Risk (default)
medium
33/100
CVSS Score
8.2 HIGH
v3.1 (nvd)
EPSS Score
0.25% LOW
0% probability 0.00%
KEV
Not listed
Ransomware
No reports
Public exploits
None found
Dark Web
Not detected

Timeline

04 Sept 2026, 16:59
Published
Vulnerability first disclosed
04 Sept 2026, 18:34
Last Modified
Vulnerability information updated

Description

undici's cache interceptor does not handle the Set-Cookie response header anywhere in its cache path, so it neither refuses to store nor strips that header. In shared cache mode, which is the default, an otherwise cacheable response that carries a Set-Cookie header, for example one marked with a public and max-age directive, is stored and then re-served to a later caller that matches the same cache key. As a result one caller's cookie is disclosed to a different caller, and an untrusted server can inject cookies into cached responses served to all subsequent callers. This violates the requirement that a shared cache must not store cookies. This affects undici versions from 7.0.0 up to 7.29.1 and from 8.0.0 up to 8.10.2. Users should upgrade to undici 7.29.1 or 8.10.2.

CVSS Metrics

  • v3.1•MEDIUM•Score: 6.5CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N
  • v3.1•HIGH•Score: 8.2CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N

EPSS Trends

Current EPSS score: 0.25%• Percentile: 16%

Techniques & Countermeasures

  • CWE-200•Exposure of Sensitive Information to an Unauthorized Actor

    The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information.

  • CWE-524•Use of Cache Containing Sensitive Information

    The code uses a cache that contains sensitive information, but the cache can be read by an actor outside of the intended control sphere.

Affected Systems

  • chainguard•node-gyp

    all | < 13.0.2-r1

  • wolfi•node-gyp

    all | < 13.0.2-r1

  • debian•node-undici

    all | all | all | < 8.10.2+dfsg+~cs3.2.2-1

  • ubuntu•node-undici

    all | all

  • nodejs•undici

    ≥ 7.0.0, < 7.29.1 | ≥ 8.0.0, < 8.10.2

  • undici•undici

    ≥ 7.0.0, < 7.29.1 | ≥ 8.0.0, < 8.10.2

References (5)