Mozilla Multiple Products Remote Code Execution Vulnerability (CVE-2010-3765)
Severity: critical · Patch status: unknown · Since 2025-10-06 · CVE-2010-3765
Mozilla Firefox, SeaMonkey, and Thunderbird contain an unspecified vulnerability when JavaScript is enabled. This 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. CISA added CVE-2010-3765 to its Known Exploited Vulnerabilities catalog on Oct 6, 2025, which means attackers are exploiting it in the wild.
What to do
- Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
- US federal agencies must remediate by Oct 27, 2025 (BOD 22-01); treat that as the outer limit.
Sources
All live incidents on Threat Watch