CVE-2026-0891
Memory safety bugs fixed in Firefox ESR 140.7, Thunderbird ESR 140.7, Firefox 147 and Thunderbird 147
Description
Memory safety bugs present in Firefox ESR 140.6, Thunderbird ESR 140.6, Firefox 146 and Thunderbird 146. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability was fixed in Firefox 147, Firefox ESR 140.7, Thunderbird 147, and Thunderbird 140.7.
No summary for this CVE yet.
CVSS Vector Breakdown
Exploitability
AV:NAttack VectorNetwork
AC:HAttack ComplexityHigh
PR:NPrivileges RequiredNone
UI:NUser InteractionNone
Scope
S:UScopeUnchanged
Impact
C:HConfidentialityHigh
I:HIntegrityHigh
A:HAvailabilityHigh
Weaknesses
Affected Products
Mozilla Corp.
oss-project·USaka Mozilla
Novell Inc.
commercial·US
Red Hat Inc.
commercial·USaka red hat
ООО «РусБИТех-Астра»
commercial·RUaka rusbitech-astra
Canonical Ltd.
commercial·GBaka canonical
АО «ИВК»
commercial·RUaka ivk
and 5 more affected products View all →
Exploitability
Official Patch Available
Attack Graph
Products CVE Techniques Tactics
Click technique nodes for MITRE ATT&CK details · drag to pan · Ctrl/⌘ + scroll to zoom, or go fullscreen.
MITRE ATT&CK
2 techniques Initial Access
Privilege Escalation
References
https://bugzilla.mozilla.org/buglist.cgi?bug_id=1964722%2C2000981%2C2003100%2C2003278
bugzilla.mozilla.org
https://www.mozilla.org/security/advisories/mfsa2026-01/
mozilla.org
https://www.mozilla.org/security/advisories/mfsa2026-03/
mozilla.org
and 38 more references View all →
Unlock Complete Vulnerability Intelligence
Get the full picture for CVE-2026-0891 and every CVE in our database. Create a free account — no credit card required.
Create Free AccountPlain-language analysis
Impact assessment and exploitation scenario in plain English
Attack graph visualization
Interactive attack path and kill chain mapping
Exploit details & PoC links
ExploitDB, Metasploit, GitHub PoCs with direct links
Nuclei scanner templates
Ready-to-use vulnerability scanner templates
Full remediation guide
Patch instructions, workarounds, and compliance impact
Interactive AI chat
Ask questions about this vulnerability in natural language
Related vulnerabilities
Semantically similar CVEs and attack patterns
REST API & MCP access
Integrate vulnerability data into your workflows