Mozilla Firefox ESR 115.35/140.10/150 Mem Safety Bug (CVE-2026-8975)
CVE-2026-8975 Published on May 19, 2026

Memory safety bugs fixed in Firefox ESR 115.36, Firefox ESR 140.11 and Firefox 151
Memory safety bugs present in Firefox ESR 115.35, Firefox ESR 140.10 and Firefox 150. 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 151, Firefox ESR 115.36, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.

NVD

Vulnerability Analysis

CVE-2026-8975 can be exploited with network access, requires user interaction. This vulnerability is consided to have a high level of attack complexity. The potential impact of an exploit of this vulnerability is considered to be very high.

Attack Vector:
NETWORK
Attack Complexity:
HIGH
Privileges Required:
NONE
User Interaction:
REQUIRED
Scope:
UNCHANGED
Confidentiality Impact:
HIGH
Integrity Impact:
HIGH
Availability Impact:
HIGH

Weakness Types

What is a Buffer Overflow Vulnerability?

The software performs operations on a memory buffer, but it can read from or write to a memory location that is outside of the intended boundary of the buffer.

CVE-2026-8975 has been classified to as a Buffer Overflow vulnerability or weakness.

What is a Memory Corruption Vulnerability?

The software writes data past the end, or before the beginning, of the intended buffer. Typically, this can result in corruption of data, a crash, or code execution. The software may modify an index or perform pointer arithmetic that references a memory location that is outside of the boundaries of the buffer. A subsequent write operation then produces undefined or unexpected results.

CVE-2026-8975 has been classified to as a Memory Corruption vulnerability or weakness.


Products Associated with CVE-2026-8975

You can be notified by email with stack.watch whenever vulnerabilities like CVE-2026-8975 are published in these products:

Mozilla Firefox
 
Mozilla Thunderbird
 
Red Hat Rhel Els
 
Red Hat Enterprise Linux Eus
 
Red Hat Enterprise Linux (RHEL)
 
Red Hat Rhel Aus
 
Red Hat Rhel Eus Long Life
 
Red Hat Rhel E4s
 
Red Hat Rhel Tus
 
Red Hat Rhel Eus
 

Affected Versions

Mozilla Firefox: Mozilla Thunderbird: Red Hat Enterprise Linux Server (v. 7 ELS): Red Hat Enterprise Linux AppStream EUS (v. 10.0): Red Hat Enterprise Linux AppStream (v. 10): Red Hat Enterprise Linux AppStream (v. 8): Red Hat Enterprise Linux AppStream AUS (v.8.4): Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4): Red Hat Enterprise Linux AppStream AUS (v.8.6): Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6): Red Hat Enterprise Linux AppStream E4S (v.8.8): Red Hat Enterprise Linux AppStream TUS (v.8.8): Red Hat Enterprise Linux AppStream E4S (v.9.2): Red Hat Enterprise Linux AppStream E4S (v.9.4): Red Hat Enterprise Linux AppStream EUS (v.9.6): Red Hat Enterprise Linux AppStream (v. 9): Red Hat Enterprise Linux 10: Red Hat Enterprise Linux 6: Red Hat Enterprise Linux 7:

Exploit Probability

EPSS
0.34%
Percentile
25.97%

EPSS (Exploit Prediction Scoring System) scores estimate the probability that a vulnerability will be exploited in the wild within the next 30 days. The percentile shows you how this score compares to all other vulnerabilities.