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-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.
Key facts
- CVSS score
- 6.8 (v2.0)
- Severity
- MEDIUM
- CVSS vector
AV:N/AC:M/Au:N/C:P/I:P/A:P- EPSS score
- 1.9% (80th percentile)
- In CISA KEV
- No
- In EU EUVD
- Yes (EUVD-2014-8476)
- Published
- January 14, 2015
- NVD last modified
- June 17, 2026
- Status
- Modified
EU Vulnerability Database (EUVD)
This vulnerability is also tracked by ENISA as EUVD-2014-8476 in the EU Vulnerability Database. Last updated in EUVD on August 6, 2024.
View on the EU Vulnerability DatabaseAffected products
- mozilla / firefox
- mozilla / firefox
- mozilla / firefox
- mozilla / firefox
- mozilla / firefox
- mozilla / firefox esr
- mozilla / seamonkey
- mozilla / thunderbird
References
- http://linux.oracle.com/errata/ELSA-2015-0046.html
- http://linux.oracle.com/errata/ELSA-2015-0047.html
- http://lists.opensuse.org/opensuse-security-announce/2015-01/msg00014.html
- http://lists.opensuse.org/opensuse-security-announce/2015-01/msg00032.html
- http://lists.opensuse.org/opensuse-security-announce/2015-01/msg00033.html
- http://lists.opensuse.org/opensuse-security-announce/2015-01/msg00036.html
- http://lists.opensuse.org/opensuse-security-announce/2015-02/msg00002.html
- http://lists.opensuse.org/opensuse-security-announce/2015-07/msg00031.html
- http://lists.opensuse.org/opensuse-updates/2015-01/msg00071.html
- http://rhn.redhat.com/errata/RHSA-2015-0046.html
- http://rhn.redhat.com/errata/RHSA-2015-0047.html
- http://secunia.com/advisories/62237
- http://secunia.com/advisories/62242
- http://secunia.com/advisories/62250
- http://secunia.com/advisories/62253
- http://secunia.com/advisories/62259
- http://secunia.com/advisories/62273
- http://secunia.com/advisories/62274
- http://secunia.com/advisories/62283
- http://secunia.com/advisories/62293
- http://secunia.com/advisories/62304
- http://secunia.com/advisories/62313
- http://secunia.com/advisories/62315
- http://secunia.com/advisories/62316
- http://secunia.com/advisories/62418
- http://secunia.com/advisories/62446
- http://secunia.com/advisories/62657
- http://secunia.com/advisories/62790
- http://www.debian.org/security/2015/dsa-3127
- http://www.debian.org/security/2015/dsa-3132
- http://www.mozilla.org/security/announce/2014/mfsa2015-04.html(Vendor Advisory)
- http://www.oracle.com/technetwork/topics/security/bulletinapr2015-2511959.html
- http://www.securityfocus.com/bid/72046
- http://www.securitytracker.com/id/1031533
- http://www.securitytracker.com/id/1031534
- http://www.ubuntu.com/usn/USN-2460-1
- https://bugzilla.mozilla.org/show_bug.cgi?id=1095859
- https://exchange.xforce.ibmcloud.com/vulnerabilities/99959
- https://security.gentoo.org/glsa/201504-01
Last updated September 17, 2026 · Source: NVD, CISA KEV, FIRST.org EPSS
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