⚠ Actively exploited
Added to CISA KEV on 2025-10-06. Federal agencies required to patch by 2025-10-27. 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..
CVE-2010-3765 — Improper Restriction of Operations within the Bounds of a Memory Buffer in Mozilla Firefox
CWE-119 — Improper Restriction of Operations within the Bounds of a Memory Buffer16 documents11 sources
Severity
9.8CRITICALNVD
EPSS
87.2%
top 0.55%
CISA KEV
KEV
Added 2025-10-06
Due 2025-10-27
Exploit
Exploited in wild
Active exploitation observed
Affected products
Timeline
PublishedOct 28
KEV addedOct 6
KEV dueOct 27
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.
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HExploitability: 3.9 | Impact: 5.9
Affected Packages3 packages
🔴Vulnerability Details
3💥Exploits & PoCs
5Exploit-DB▶
Mozilla Firefox 3.6.8 < 3.6.11 - Interleaving 'document.write' / 'appendChild' Remote Overflow↗2010-10-29
Exploit-DB
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