CVE-2026-85077: sanic · HTTP Request/Response Splitting
Affects sanicSource CVE Database V5
Not known to be exploited · CVSS 8.2 High : upgrade to 25.12.1 or 24.12.1 soon.
Data as of 1 Nov 2026, 22:58 UTC
- EPSS
- 0.4% chance of exploitation in 30 days – higher than 41% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 25.12.1, 24.12.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:NExploitation evidence
Disclosed: evidence found.
CVE published 17 Sep 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 1 Nov 2026.
What to do
Upgrade sanic to 25.12.1 or 24.12.1.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| sanic-orgsanic | Affected
| Fixed in
|
| sanic-orgsanic | Affected
| Fixed in
|
PyPIsanicpkg:pypi/sanicOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Upgrade Sanic to version 24.12.1 or later, or to version 25.12.1 or later. These versions contain the official fix that properly neutralizes CRLF sequences in HTTP headers. No other mitigation is required once patched.
Description
Sanic is an opensource python web server/framework. Prior to version 24.12.1, and in version 25.12.0, the HTTP/1.1 response pipeline in sanic/response/types.py serializes response header names and values without rejecting carriage-return or line-feed characters. Applications that place attacker-controlled data in response.headers, file(..., filename=...), or cookie path and domain attributes can therefore emit injected headers and may split responses. Depending on application and proxy behavior, this can enable session fixation through injected cookies, cache poisoning, or security-header corruption. This issue is fixed in versions 24.12.1 and 25.12.1.
References
- github.com/sanic-org/sanic/security/advisories/GHSA-m64h-22vf-48wm (opens in a new tab)
- github.com/sanic-org/sanic/pull/3164 (opens in a new tab)
- github.com/sanic-org/sanic/pull/3165 (opens in a new tab)
- github.com/sanic-org/sanic/commit/47349d689d65fa1907977ac100e867894aeafb22 (opens in a new tab)
- github.com/sanic-org/sanic/commit/9a95bb1c187558949606b915f5162c15f2db781b (opens in a new tab)
- github.com/sanic-org/sanic/commit/a332796506c7c588b6930b02a8886e43eb8ea8d6 (opens in a new tab)
- github.com/sanic-org/sanic/releases/tag/v24.12.1 (opens in a new tab)
- github.com/sanic-org/sanic/releases/tag/v25.12.1 (opens in a new tab)