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CVE-2010-3765

9.8, critical Known exploited

Mozilla Multiple Products Remote Code Execution Vulnerability

NVD (opens in a new tab) CVE.org (opens in a new tab) CISA KEV catalogue (opens in a new tab)
CVSS
9.8, critical critical CVSS v3.1
EPSS, next 30 days
83% higher than 99.6% of scored CVEs
Exploitation
Confirmed in the wild
Published
28 Oct 201015 years ago

Known exploited

CISA added this to the Known Exploited Vulnerabilities Catalog on 6 Oct 2025. US federal agencies had to remediate by 27 Oct 2025, a deadline that has passed.

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.

Details

Vendor
Mozilla
Product
Firefox
Weakness
CWE-119 (opens in a new tab)
Status
Analyzed
Updated
16 Jun 2026
Assigner
cve@mitre.org

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

References 52

Exploit code 3

Advisories 42

34 more

Other references 7

The kind is read from NVD's tags where present and from the shape of the URL otherwise, so treat it as a hint.

Other Mozilla CVEs

Every Mozilla CVE we hold

Same vendor in what we hold, not a known link between the flaws.

  • CVE-2024-9680 Mozilla Firefox Use-After-Free Vulnerability KEV EPSS 23% 9.8, critical
  • CVE-2022-26485 Mozilla Firefox Use-After-Free Vulnerability KEV EPSS 14% 8.8, high
  • CVE-2022-26486 Mozilla Firefox Use-After-Free Vulnerability KEV EPSS 2% 9.6, critical
  • CVE-2020-6819 Mozilla Firefox And Thunderbird Use-After-Free Vulnerability KEV EPSS 3% 8.1, high
  • CVE-2020-6820 Mozilla Firefox And Thunderbird Use-After-Free Vulnerability KEV EPSS 7% 8.1, high
  • CVE-2019-17026 Mozilla Firefox And Thunderbird Type Confusion Vulnerability KEV EPSS 46% 8.8, high
  • CVE-2019-11707 Mozilla Firefox and Thunderbird Type Confusion Vulnerability KEV EPSS 38% 8.8, high
  • CVE-2019-11708 Mozilla Firefox and Thunderbird Sandbox Escape Vulnerability KEV EPSS 56% 10, critical

Beyond this page

Is CVE-2010-3765 in your network?

This page tells you how dangerous CVE-2010-3765 is out there. Whether it sits on one of your devices, only a scan of your own network can tell. That is what our systems do, every day, for the companies we protect.

CVE-2010-3765 is in the CISA catalogue of exploited vulnerabilities: attackers are already exploiting it.

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    Detect it if it's exploited

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Check your exposure

Assembled from the NVD 2.0 API, the CISA Known Exploited Vulnerabilities Catalog and FIRST EPSS. Scores are as of our last collection on 17 Oct 2026, not the live upstream state.