CVE-2025-8040

Memory safety bugs fixed in Firefox ESR 140.1, Thunderbird ESR 140.1, Firefox 141 and Thunderbird 141

Severity Score

8.8

*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 ESR 140.0, Thunderbird ESR 140.0, Firefox 140 and Thunderbird 140. 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 < 141, Firefox ESR < 140.1, Thunderbird < 141, and Thunderbird < 140.1.

Memory safety bugs present in Firefox ESR 140.0, Thunderbird ESR 140.0, Firefox 140 and Thunderbird 140. 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 141, Firefox ESR 140.1, Thunderbird 141, and Thunderbird 140.1.

These are all security issues fixed in the MozillaThunderbird-140.1.0-1.1 package on the GA media of openSUSE Tumbleweed.

*Credits: Andrew McCreight, Ashley Zebrowski

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

Required

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Attack Vector

Network

Attack Complexity

Low

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

2025-07-22 CVE Reserved
2025-07-22 CVE Published
2026-04-13 CVE Updated
2026-05-08 EPSS Updated
---------- Exploited in Wild
---------- KEV Due Date
---------- First Exploit

CWE

CWE-119: Improper Restriction of Operations within the Bounds of a Memory Buffer

CAPEC

References (6)

URL	Tag	Source
https://bugzilla.mozilla.org/buglist.cgi?bug_id=1975058%2C1975058%2C1975998%2C1975998
https://www.mozilla.org/security/advisories/mfsa2025-56
https://www.mozilla.org/security/advisories/mfsa2025-59
https://www.mozilla.org/security/advisories/mfsa2025-61
https://www.mozilla.org/security/advisories/mfsa2025-63
https://bugzilla.mozilla.org/buglist.cgi?bug_id=1975058%2C1975998

URL	Date	SRC

URL	Date	SRC

URL	Date	SRC

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
Canonical Search vendor "Canonical"		Ubuntu Linux Search vendor "Canonical" for product "Ubuntu Linux"				*		-		Affected
Fedoraproject Search vendor "Fedoraproject"		Fedora Search vendor "Fedoraproject" for product "Fedora"				*		-		Affected
Freebsd Search vendor "Freebsd"		Freebsd Search vendor "Freebsd" for product "Freebsd"				*		-		Affected
Opensuse Search vendor "Opensuse"		Leap Search vendor "Opensuse" for product "Leap"				*		-		Affected
Slackware Search vendor "Slackware"		Slackware Linux Search vendor "Slackware" for product "Slackware Linux"				*		-		Affected
Suse Search vendor "Suse"		Packagehub Search vendor "Suse" for product "Packagehub"				*		-		Affected
Suse Search vendor "Suse"		Sle-module-desktop-applications Search vendor "Suse" for product "Sle-module-desktop-applications"				*		-		Affected
Suse Search vendor "Suse"		Sle-we Search vendor "Suse" for product "Sle-we"				*		-		Affected
Suse Search vendor "Suse"		Sle Hpc-espos Search vendor "Suse" for product "Sle Hpc-espos"				*		-		Affected
Suse Search vendor "Suse"		Sle Hpc-ltss Search vendor "Suse" for product "Sle Hpc-ltss"				*		-		Affected
Suse Search vendor "Suse"		Sle Hpc Search vendor "Suse" for product "Sle Hpc"				*		-		Affected
Suse Search vendor "Suse"		Sled Search vendor "Suse" for product "Sled"				*		-		Affected
Suse Search vendor "Suse"		Sles-ltss-extended-security Search vendor "Suse" for product "Sles-ltss-extended-security"				*		-		Affected
Suse Search vendor "Suse"		Sles-ltss Search vendor "Suse" for product "Sles-ltss"				*		-		Affected
Suse Search vendor "Suse"		Sles Search vendor "Suse" for product "Sles"				*		-		Affected
Suse Search vendor "Suse"		Sles Sap Search vendor "Suse" for product "Sles Sap"				*		-		Affected