CVE-2025-0243

firefox: thunderbird: Memory safety bugs fixed in Firefox 134, Thunderbird 134, Firefox ESR 128.6, and Thunderbird 128.6

Severity Score

5.1

*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

*Multiple Sources

Exploited in Wild

*KEV

Decision

Track*

*SSVC

Descriptions

Memory safety bugs present in Firefox 133, Thunderbird 133, Firefox ESR 128.5, and Thunderbird 128.5. 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 affects Firefox < 134 and Firefox ESR < 128.6.

A flaw was found in Firefox. The Mozilla Foundation's Security Advisory describes the following issue: Memory safety bugs present in Firefox 133, Thunderbird 133, Firefox ESR 128.5, and Thunderbird 128.5. 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.

Multiple security issues have been found in the Mozilla Firefox web browser, which could potentially result in the execution of arbitrary code or privilege escalation.

*Credits: Andrew Osmond and the Mozilla Fuzzing Team

CVSS Scores

Attack Vector

Local

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

Low

Integrity

Low

Availability

None

Attack Vector

Network

Attack Complexity

High

Privileges Required

None

User Interaction

Required

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Attack Vector

Network

Attack Complexity

High

Authentication

None

Confidentiality

Complete

Integrity

Complete

Availability

Complete

* Common Vulnerability Scoring System

SSVC

Decision:Track*

Exploitation

None

Automatable

Tech. Impact

Total

* Organization's Worst-case Scenario

Timeline

2025-01-06 CVE Reserved
2025-01-07 CVE Published
2025-01-08 EPSS Updated
2025-01-09 CVE Updated
---------- Exploited in Wild
---------- KEV Due Date
---------- First Exploit

CWE

CWE-120: Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')

CAPEC

References (7)

URL	Tag	Source
https://bugzilla.mozilla.org/buglist.cgi?bug_id=1827142%2C1932783
https://www.mozilla.org/security/advisories/mfsa2025-01
https://www.mozilla.org/security/advisories/mfsa2025-02
https://www.mozilla.org/security/advisories/mfsa2025-04
https://www.mozilla.org/security/advisories/mfsa2025-05

URL	Date	SRC

URL	Date	SRC

URL	Date	SRC
https://access.redhat.com/security/cve/CVE-2025-0243	2025-01-09
https://bugzilla.redhat.com/show_bug.cgi?id=2336175	2025-01-09

Affected Vendors, Products, and Versions

Vendor		Product				Version		Other		Status
Vendor	Product	Version	Other	Status	<-- -->	Vendor	Product	Version	Other	Status
Mozilla Search vendor "Mozilla"		Firefox Search vendor "Mozilla" for product "Firefox"				*		-		Affected
Mozilla Search vendor "Mozilla"		Firefox Esr Search vendor "Mozilla" for product "Firefox Esr"				*		-		Affected
Mozilla Search vendor "Mozilla"		Thunderbird Search vendor "Mozilla" for product "Thunderbird"				*		-		Affected
Mozilla Search vendor "Mozilla"		Thunderbird Esr Search vendor "Mozilla" for product "Thunderbird Esr"				*		-		Affected
Redhat Search vendor "Redhat"		Enterprise Linux Search vendor "Redhat" for product "Enterprise Linux"				*		-		Affected
Redhat Search vendor "Redhat"		Rhel Aus Search vendor "Redhat" for product "Rhel Aus"				*		-		Affected
Redhat Search vendor "Redhat"		Rhel E4s Search vendor "Redhat" for product "Rhel E4s"				*		-		Affected
Redhat Search vendor "Redhat"		Rhel Eus Search vendor "Redhat" for product "Rhel Eus"				*		-		Affected
Redhat Search vendor "Redhat"		Rhel Tus Search vendor "Redhat" for product "Rhel Tus"				*		-		Affected
Canonical Search vendor "Canonical"		Ubuntu Linux Search vendor "Canonical" for product "Ubuntu Linux"				*		-		Affected
Debian Search vendor "Debian"		Debian Linux Search vendor "Debian" for product "Debian Linux"				*		-		Affected
Fedoraproject Search vendor "Fedoraproject"		Fedora Search vendor "Fedoraproject" for product "Fedora"				*		-		Affected
Redhat Search vendor "Redhat"		Enterprise Linux Search vendor "Redhat" for product "Enterprise Linux"				*		-		Affected
Redhat Search vendor "Redhat"		Rhel Aus Search vendor "Redhat" for product "Rhel Aus"				*		-		Affected
Redhat Search vendor "Redhat"		Rhel E4s Search vendor "Redhat" for product "Rhel E4s"				*		-		Affected
Redhat Search vendor "Redhat"		Rhel Els Search vendor "Redhat" for product "Rhel Els"				*		-		Affected
Redhat Search vendor "Redhat"		Rhel Eus Search vendor "Redhat" for product "Rhel Eus"				*		-		Affected
Redhat Search vendor "Redhat"		Rhel Tus Search vendor "Redhat" for product "Rhel Tus"				*		-		Affected
Slackware Search vendor "Slackware"		Slackware Linux Search vendor "Slackware" for product "Slackware Linux"				*		-		Affected
Suse Search vendor "Suse"		Sles-ltss-extended-security Search vendor "Suse" for product "Sles-ltss-extended-security"				*		-		Affected