---
id: CVE-2026-85077
title: Sanic is an opensource python web server/framework
summary: >-
  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…
severity: high
cvss: 8.2
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:N'
cwe:
  - CWE-113
  - CWE-93
vendor: sanic-org
product: sanic
affected:
  - sanic < 24.12.1
  - 'sanic >= 25.12.0, < 25.12.1'
published: '2026-09-17'
updated: '2026-09-24'
sourceUpdated: '2026-09-24T21:22:19.873'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-85077'
references:
  - url: >-
      https://github.com/sanic-org/sanic/commit/47349d689d65fa1907977ac100e867894aeafb22
    label: security-advisories@github.com
  - url: >-
      https://github.com/sanic-org/sanic/commit/9a95bb1c187558949606b915f5162c15f2db781b
    label: security-advisories@github.com
  - url: >-
      https://github.com/sanic-org/sanic/commit/a332796506c7c588b6930b02a8886e43eb8ea8d6
    label: security-advisories@github.com
  - url: 'https://github.com/sanic-org/sanic/pull/3164'
    label: security-advisories@github.com
  - url: 'https://github.com/sanic-org/sanic/pull/3165'
    label: security-advisories@github.com
  - url: 'https://github.com/sanic-org/sanic/releases/tag/v24.12.1'
    label: security-advisories@github.com
  - url: 'https://github.com/sanic-org/sanic/releases/tag/v25.12.1'
    label: security-advisories@github.com
  - url: 'https://github.com/sanic-org/sanic/security/advisories/GHSA-m64h-22vf-48wm'
    label: security-advisories@github.com
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-85077.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-85077'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-85077'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-85077'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2536070'
tags:
  - nvd
  - cve.org
  - csaf
  - vex
  - red-hat
epss: 0.00485
epssPercentile: 0.39098
ssvc:
  exploitation: none
  automatable: 'yes'
  technicalImpact: partial
  timestamp: '2026-09-21T20:45:00.743376Z'
ingestedAt: '2026-09-17T15:20:39.000Z'
---

## Overview

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.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.

## Vendor advisories

- **Red Hat VEX** · updated 2026-09-17 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-85077.json)