---
title: "CVE-2010-3765: Mozilla Multiple Products Remote Code Execution Vulnerability"
url: https://erroneo.us/security/cve/CVE-2010-3765/
description: "CVE-2010-3765 (Mozilla Multiple Products): Exploited in the wild (CISA KEV). Mozilla Firefox 3.5.x through 3.5.14 and 3.6.x through 3.6.11, Thunderbird…"
type: vulnerability-record
section: "Security Digest"
date_published: 2010-10-27
date_modified: 2025-10-22
publisher: erroneo.us
author: erroneo.us Security Desk
cve: "CVE-2010-3765"
kev: true
cvss: 9.8
epss: 0.83156
license: All rights reserved. Quote with attribution and a link.
---

# CVE-2010-3765: Mozilla Multiple Products Remote Code Execution Vulnerability

**Signal:** Exploited: patch now if you run it. CISA has confirmed exploitation in the wild. (Computed from CISA KEV, EPSS and CVSS; not an editorial verdict.)

## Should you act?

- Yes, if you run Mozilla Multiple Products. CISA added this CVE to its Known Exploited Vulnerabilities catalog on 2025-10-06, which means there is reliable evidence of exploitation in the wild. US federal agencies must remediate by 2025-10-27 ; treat that as the outer limit, not the target.
- EPSS 83.2% , percentile 99.7: FIRST’s model estimates a 83.2% chance of exploitation activity in the next 30 days, higher than 99.7% of all scored CVEs (very high). EPSS is a probability, not a verdict.
- Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.

## What it is

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.

## Affected products (CVE record)

- n/a n/a: see advisory

## Severity

- CISA-ADP CVSS 3.1: 9.8 `CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`

## Exploitation

- CISA KEV: added 2025-10-06; federal due date 2025-10-27. Known ransomware use: Unknown.
- CISA 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.
- CISA SSVC assessment: exploitation active , automatable yes , technical impact total .
- FIRST EPSS (model of 2026-10-21): 83.16% probability of exploitation activity in the next 30 days; percentile 99.7.

## Sources

- [RHSA-2010:0812](https://rhn.redhat.com/errata/RHSA-2010-0812.html)
- [RHSA-2010:0896](http://www.redhat.com/support/errata/RHSA-2010-0896.html)
- [RHSA-2010:0808](http://www.redhat.com/support/errata/RHSA-2010-0808.html)
- [FEDORA-2010-17105](http://lists.fedoraproject.org/pipermail/package-announce/2010-November/050233.html)
- [USN-1011-3](http://www.ubuntu.com/usn/USN-1011-3)
- [USN-1011-1](http://www.ubuntu.com/usn/usn-1011-1)
- [USN-1011-2](http://www.ubuntu.com/usn/USN-1011-2)
- [RHSA-2010:0809](http://www.redhat.com/support/errata/RHSA-2010-0809.html)
- [MDVSA-2010:219](http://www.mandriva.com/security/advisories?name=MDVSA-2010:219)
- [DSA-2124](http://www.debian.org/security/2010/dsa-2124)
- [MDVSA-2010:213](http://www.mandriva.com/security/advisories?name=MDVSA-2010:213)
- [FEDORA-2010-16883](http://lists.fedoraproject.org/pipermail/package-announce/2010-October/050061.html)
- [SSA:2010-305-01](http://slackware.com/security/viewer.php?l=slackware-security&y=2010&m=slackware-security.556706)
- [RHSA-2010:0810](http://www.redhat.com/support/errata/RHSA-2010-0810.html)
- [FEDORA-2010-16897](http://lists.fedoraproject.org/pipermail/package-announce/2010-October/050077.html)
- [RHSA-2010:0861](http://www.redhat.com/support/errata/RHSA-2010-0861.html)
- [FEDORA-2010-16885](http://lists.fedoraproject.org/pipermail/package-announce/2010-October/050154.html)
- [Listed in CISA KEV notes (mozilla.org)](https://www.mozilla.org/en-US/security/advisories/mfsa2010-73)
- [CVE.org record CVE-2010-3765](https://www.cve.org/CVERecord?id=CVE-2010-3765)
- [NVD entry CVE-2010-3765](https://nvd.nist.gov/vuln/detail/CVE-2010-3765)
- [CISA Known Exploited Vulnerabilities catalog entry](https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2010-3765)
- [44425](http://www.securityfocus.com/bid/44425)
- [bugzilla.mozilla.org](https://bugzilla.mozilla.org/show_bug.cgi?id=607222#c53)
- [ADV-2010-2837](http://www.vupen.com/english/advisories/2010/2837)
- [bugzilla.redhat.com](https://bugzilla.redhat.com/show_bug.cgi?id=646997)
- [support.avaya.com](http://support.avaya.com/css/P8/documents/100114335)
- [41965](http://secunia.com/advisories/41965)
- [41975](http://secunia.com/advisories/41975)
- [15341](http://www.exploit-db.com/exploits/15341)
- [1024651](http://www.securitytracker.com/id?1024651)
- [41761](http://secunia.com/advisories/41761)
- [bugzilla.mozilla.org](https://bugzilla.mozilla.org/show_bug.cgi?id=607222)
- [norman.com](http://norman.com/about_norman/press_center/news_archive/2010/129223/en?utm_source=twitterfeed&utm_medium=twitter)
- [41969](http://secunia.com/advisories/41969)
- [blogs.sun.com](http://blogs.sun.com/security/entry/multiple_vulnerabilities_in_mozilla_firefox)
- [norman.com](http://www.norman.com/about_norman/press_center/news_archive/2010/129223/)
- [1024650](http://www.securitytracker.com/id?1024650)
- [42867](http://secunia.com/advisories/42867)
- [blog.mozilla.com](http://blog.mozilla.com/security/2010/10/26/critical-vulnerability-in-firefox-3-5-and-firefox-3-6/)
- [ADV-2010-2857](http://www.vupen.com/english/advisories/2010/2857)
- [ADV-2011-0061](http://www.vupen.com/english/advisories/2011/0061)
- [support.avaya.com](http://support.avaya.com/css/P8/documents/100114329)
- [1024645](http://www.securitytracker.com/id?1024645)
- [42043](http://secunia.com/advisories/42043)
- [norman.com](http://www.norman.com/security_center/virus_description_archive/129146/)
- [41966](http://secunia.com/advisories/41966)
- [42008](http://secunia.com/advisories/42008)
- [ADV-2010-2871](http://www.vupen.com/english/advisories/2010/2871)
- [isc.sans.edu](http://isc.sans.edu/diary.html?storyid=9817)
- [mozilla.org](http://www.mozilla.org/security/announce/2010/mfsa2010-73.html)
- [15352](http://www.exploit-db.com/exploits/15352)
- [oval:org.mitre.oval:def:12108](https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A12108)
- [42003](http://secunia.com/advisories/42003)
- [15342](http://www.exploit-db.com/exploits/15342)
- [ADV-2010-2864](http://www.vupen.com/english/advisories/2010/2864)

---
Source page: https://erroneo.us/security/cve/CVE-2010-3765/ · Security Digest: https://erroneo.us/security/ · More: https://erroneo.us/llms.txt