Vulnerability Description
Tornado before 6.6 does not validate the max_age argument of RequestHandler.set_cookie (also called by set_signed_cookie, set_secure_cookie, and clear_cookie), allowing injection of additional Set-Cookie attributes. When an application passes attacker-influenced input as max_age, an attacker can embed attributes such as Domain, Path, or Secure to widen the cookie's scope to parent paths or other subdomains.
CVSS Score
MEDIUM
Related Weaknesses (CWE)
References
- https://github.com/tornadoweb/tornado/security/advisories/GHSA-c6v4-qj2h-f748
- https://www.vulncheck.com/advisories/tornado-before-6.6-cookie-attribute-injecti
FAQ
What is CVE-2026-123535?
CVE-2026-123535 is a vulnerability with a CVSS score of 4.2 (MEDIUM). Tornado before 6.6 does not validate the max_age argument of RequestHandler.set_cookie (also called by set_signed_cookie, set_secure_cookie, and clear_cookie), allowing injection of additional Set-Coo...
How severe is CVE-2026-123535?
CVE-2026-123535 has been rated MEDIUM with a CVSS base score of 4.2/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-123535?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.