CVE-2010-3765

mozilla firefox, mozilla thunderbird, mozilla seamonkey

Published 28 Oct 2010 · updated 16 Jun 2026 · Analyzed

9.8 Critical · CVSS 3.1, CISA ADP

Exploited in the wild

CISA added this to its Known Exploited Vulnerabilities catalog on 6 Oct 2025, with a remediation deadline of 27 Oct 2025 for US federal agencies.

Required action: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

Description

Mozilla Firefox 3.5.x through 3.5.14 and 3.6.x through 3.6.11, Thunderbird 3.1.6 before 3.1.6 and 3.0.x before 3.0.10, and SeaMonkey 2.x before 2.0.10, when JavaScript is enabled, allows remote attackers to execute arbitrary code via vectors related to nsCSSFrameConstructor::ContentAppended, the appendChild method, incorrect index tracking, and the creation of multiple frames, which triggers memory corruption, as exploited in the wild in October 2010 by the Belmoo malware.

References

blog.mozilla.com/security/2010/10/26/critical-vulnerability-in-firefox-3-5-and-firefox-3-6/ · Vendor Advisory
blogs.sun.com/security/entry/multiple_vulnerabilities_in_mozilla_firefox · Broken Link
isc.sans.edu/diary.html?storyid=9817 · Press/Media Coverage
lists.fedoraproject.org/pipermail/package-announce/2010-November/050233.html · Third Party Advisory
lists.fedoraproject.org/pipermail/package-announce/2010-October/050061.html · Third Party Advisory
lists.fedoraproject.org/pipermail/package-announce/2010-October/050077.html · Third Party Advisory
lists.fedoraproject.org/pipermail/package-announce/2010-October/050154.html · Third Party Advisory
norman.com/about_norman/press_center/news_archive/2010/129223/en?utm_source=twitterfeed&utm_medium=twitter · Product
secunia.com/advisories/41761 · Vendor Advisory
secunia.com/advisories/41965 · Vendor Advisory
secunia.com/advisories/41966 · Vendor Advisory
secunia.com/advisories/41969 · Vendor Advisory
secunia.com/advisories/41975 · Vendor Advisory
secunia.com/advisories/42003 · Vendor Advisory
secunia.com/advisories/42008 · Vendor Advisory
secunia.com/advisories/42043 · Vendor Advisory
secunia.com/advisories/42867 · Vendor Advisory
slackware.com/security/viewer.php?l=slackware-security&y=2010&m=slackware-security.556706 · Third Party Advisory
support.avaya.com/css/P8/documents/100114329 · Third Party Advisory
support.avaya.com/css/P8/documents/100114335 · Third Party Advisory
www.debian.org/security/2010/dsa-2124 · Third Party Advisory
www.exploit-db.com/exploits/15341 · Exploit
www.exploit-db.com/exploits/15342 · Exploit
www.exploit-db.com/exploits/15352 · Exploit
www.mandriva.com/security/advisories?name=MDVSA-2010:213 · Third Party Advisory