CVE-2026-16729 (GCVE-0-2026-16729)

Vulnerability from cvelistv5 – Published: 2026-07-29 16:45 – Updated: 2026-07-29 18:08
VLAI
Title
undici vulnerable to cookie attribute injection via unsanitized domain and unparsed setCookie fields
Summary
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.
Severity
4.8 (Medium)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-29 18:08 UTC
CWE
  • CWE-74 - Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')
Assigner
openjs CNA under the redhat root
CNA scorecard C 65/100 over 127 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
undici undici Affected: 0 , < 6.28.0 (semver)
Unaffected: 6.28.0 (semver)
Affected: 7.0.0 , < 7.29.0 (semver)
Unaffected: 7.29.0 (semver)
Affected: 8.0.0 , < 8.9.0 (semver)
Unaffected: 8.9.0 (semver)
guessed Create a notification for this product.
Credits
Zelys-DFKH mcollina UlisesGascon
Show details on NVD website
To clipboard 

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    Related by attack behaviour

    Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.