PatchTheCVECVE-2026-35536: In Tornado before 6.5.5, cookie attribute injection could occur because the domain, path, and samesite argumen
CVE-2026-35536 is a high-severity flaw (CVSS 7.2) affecting tornado. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
In Tornado before 6.5.5, cookie attribute injection could occur because the domain, path, and samesite arguments to .RequestHandler.set_cookie were not checked for crafted characters.
Why this priority
- High severity
- Remotely exploitable, no login, no user action
A fixed release or distro patch exists.
Risk facts
| CVSS score | 7.2 (High) |
| Attack vector | Network (remote) |
| Attack complexity | Low |
| Privileges needed | None |
| User interaction | None |
| EPSS exploit chance | 0.2% (top 85%) |
| CISA exploited list | No |
| Weakness | CWE-159 |
| Published | 2026-04-03 |
| Last modified | 2026-07-24 |
Last updated 2026-07-24 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score
Am I affected?
Timeline
- Published CVE record published
- Updated Record last modified
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Quick answers
How do I fix CVE-2026-35536?
tornado: upgrade to 6.5.5. Exact commands for each OS are on this page.
Is CVE-2026-35536 being exploited?
CVE-2026-35536 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.
What does CVE-2026-35536 affect?
CVE-2026-35536 affects tornado. Severity is high (CVSS 7.2). In Tornado before 6.5.5, cookie attribute injection could occur because the domain, path, and samesite arguments to .RequestHandler.set_cookie were not checked for crafted characters.
How urgent is CVE-2026-35536?
Priority 34/100. High severity; Remotely exploitable, no login, no user action