undici vulnerable to cookie attribute injection via unsanitized domain and unparsed setCookie fields (undici undici)

CVE-2026-16729
MEDIUM 4.8

At a glance

Source
NVD
EPSS
EPSS 0.28 % · percentile 20 ()
State
PUBLISHED
Published
Updated
Assigner
openjs
NVD status
Analyzed

Description

undici's setCookie function does not fully sanitize cookie attributes. In undici before 6.28.0, from 7.0.0 up to before 7.29.0, and from 8.0.0 up to before 8.9.0, a domain value is not checked for semicolons and entries in the unparsed array are not sanitized, so attacker-influenced input can inject additional cookie attributes. For example, a domain value containing a semicolon can append attributes such as SameSite, and an unparsed entry can inject attributes such as HttpOnly, without the caller setting them. Applications that pass user-controlled input to these fields, such as multi-tenant or reverse-proxy servers that scope session cookies to a tenant-supplied domain, can have SameSite CSRF protections bypassed, or the Secure, HttpOnly, and SameSite attributes forced, stripped, or overridden. The issue is fixed in undici 6.28.0, 7.29.0, and 8.9.0.

Weaknesses (CWE)

  • CWE-74 — Improper Neutralization of Special Elements in Output Used by a Downstream Component

References

Scores

VersionScoreVectorScored by
CVSS 3.1MEDIUM 4.8CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:Nopenjs
CVSS 3.1MEDIUM 4.8CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:NNVD · ce714d77-add3-4f53-aff5-83d477b104bb (Secondary)
CVSS 3.1MEDIUM 6.5CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:NNVD · nvd@nist.gov (Primary)

Advisories

European references

CERT-FR advisories

Affected configurations (NVD CPE)

Affected products

ProductVersions
undici · undiciaffected 0 < 6.28.0 ; unaffected 6.28.0 ; affected 7.0.0 < 7.29.0 ; unaffected 7.29.0 ; affected 8.0.0 < 8.9.0 ; unaffected 8.9.0

Sources

SourceLicence
CVE List (CVEProject cvelistV5)CVE Program Terms of Use
EPSS (FIRST.org)FIRST — attribution requested
ENISA EUVDENISA — reproduction authorised, source acknowledged
CERT-FR (ANSSI)Licence Ouverte / Etalab 2.0
NVD (NIST) via fkie-cad/nvd-json-data-feedsPublic domain — this product uses data from the NVD API but is not endorsed or certified by the NVD