Threats / Mozilla / CVE-2010-3765
CVE-2010-3765
· EUVD no mirror located
· GCVE no mirror located
Verified 2026-08-04
Mozilla Multiple Products vulnerability
Mozilla Firefox, SeaMonkey, and Thunderbird contain a memory corruption vulnerability in JavaScript frame construction that allows remote code execution when JavaScript is enabled.
Verdict
Today item — known-exploited.
Remote attackers can execute arbitrary code by exploiting incorrect index tracking in nsCSSFrameConstructor::ContentAppended during DOM manipulation, triggering memory corruption through multiple frame creation.
CISA KEV Yes · 2025-10-064EPSS 0.83279 (verify live)5CVSS 9.8 (CISA)3CISA SSVC Exploitation: active · Automatable: yes · Impact: total3Exploit Weaponized · public exploit · Metasploit module12
01
Is it exploitable?
— the evidence, ranked above the scoreReported exploitation
5 independent public reports of in-the-wild exploitation are cataloged.Distinct reporting sources (vendor, incident response, government); open them for the underlying claims.
Exploited in the wild
Listed in the CISA Known Exploited Vulnerabilities catalog (added 2025-10-06).
Probability (EPSS)
EPSS 0.83279 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
CVSS 9.8 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H) · Affected: Mozilla, Multiple Products. Confirm exact fixed builds in the vendor advisory.CVSS — CISA-assigned via the ADP container (CVE.org), version 3.1; the CNA left no metrics, so CISA's own score is used ahead of NVD.
CISA SSVC (triage disposition)
Exploitation: active · Automatable: yes · Technical Impact: totalCISA's own stakeholder-specific triage inputs, published in the CVE record (CISA Coordinator role). NOTE: this is CISA's three decision points; the final Act/Attend/Track decision also requires a Mission & Well-being input not published here, so no overall decision is asserted.
Currency of the record
CISA added this to its KEV catalog 5458 days after the CVE record was published.KEV lag = CISA-KEV dateAdded − CVE.org datePublished; a floor on how long the known-exploited flaw sat in the public record before the federal catalog listed it. Severity/weakness here is CNA- or CISA-assigned (current at disclosure), independent of NVD's analysis backlog.
Public exploit available
Public exploit tooling is catalogued for this CVE (a functional/weaponized public exploit). Catalog entries: Metasploit module. We link the catalog page(s) only — no payload or code is hosted or restated here.Link, never host — the catalog page is the source; basicsecurity.net does not redistribute payloads.
02
Who’s exploiting it?
— attribution turns risk into urgencyAttribution not established
No confirmed (advisory-backed) threat-actor attribution is established for this record. Absence of a named actor is not absence of compromise — see Coverage & confidence.
03
Why it matters
— the attack path, told twice: adversary, then board1
Front door — unauthenticated access narrative 1
Attacker
I craft a malicious webpage containing JavaScript that manipulates the DOM via appendChild to trigger incorrect frame indexing.
Business
Users visiting the attacker's site with JavaScript enabled face arbitrary code execution on their systems.
2
Keys to the kingdom — privilege/identity takeover narrative 2
Attacker
I exploit the memory corruption to gain code execution within the browser process with user privileges.
Business
Attackers gain ability to steal credentials, install malware, or pivot to other systems on the user's network.
04
What to do
— defensible action- Remediate per the vendor advisory — confirm the fixed build for your version and verify exposure.1
Say it to the boardA vulnerability with this evidence profile is a defensible budget line, not a backlog ticket — fund the change against the proof above.
05