CVE-2025-5269
published 2025-05-27CVE-2025-5269: Memory safety bug present in Firefox ESR 128.10, and Thunderbird 128.10. This bug showed evidence of memory corruption and we presume that with enough effort…
PriorityP344high8.1CVSS 3.1
AVNACHPRNUINSUCHIHAH
EPSS
0.40%
32.9th percentile
Memory safety bug present in Firefox ESR 128.10, and Thunderbird 128.10. This bug showed evidence of memory corruption and we presume that with enough effort this could have been exploited to run arbitrary code. This vulnerability was fixed in Firefox ESR 128.11 and Thunderbird 128.11.
Affected
9 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | firefox-esr | < firefox-esr 128.11.0esr-1~deb12u1 (bookworm) | firefox-esr 128.11.0esr-1~deb12u1 (bookworm) |
| debian | thunderbird | < firefox-esr 128.11.0esr-1~deb12u1 (bookworm) | firefox-esr 128.11.0esr-1~deb12u1 (bookworm) |
| mozilla | firefox | < 128.11.0 | 128.11.0 |
| mozilla | firefox | — | — |
| mozilla | thunderbird | < 128.11.0 | 128.11.0 |
| mozilla | thunderbird | >= 0 < 1:128.11.0esr-1~deb11u1 | 1:128.11.0esr-1~deb11u1 |
| mozilla | thunderbird | >= 0 < 1:128.11.0esr-1~deb12u1 | 1:128.11.0esr-1~deb12u1 |
| mozilla | thunderbird | >= 0 < 1:128.11.0esr-1 | 1:128.11.0esr-1 |
| mozilla | thunderbird | >= 0 < 1:128.11.0esr-1 | 1:128.11.0esr-1 |
CVSS provenance
nvdv3.18.1HIGHCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
osv8.1HIGH
vendor_debian8.1HIGH
vendor_redhat8.1HIGH
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OSV
CVE-2025-5269: Memory safety bug present in Firefox ESR 128
osv·2025-05-27·CVSS 8.1
CVE-2025-5269 [HIGH] CVE-2025-5269: Memory safety bug present in Firefox ESR 128
Memory safety bug present in Firefox ESR 128.10, and Thunderbird 128.10. This bug showed evidence of memory corruption and we presume that with enough effort this could have been exploited to run arbitrary code. This vulnerability affects Firefox ESR < 128.11 and Thunderbird < 128.11.
GHSA
GHSA-qjw8-8452-9587: Memory safety bug present in Firefox ESR 128
ghsa_unreviewed·2025-05-27
CVE-2025-5269 [MEDIUM] CWE-787 GHSA-qjw8-8452-9587: Memory safety bug present in Firefox ESR 128
Memory safety bug present in Firefox ESR 128.10, and Thunderbird 128.10. This bug showed evidence of memory corruption and we presume that with enough effort this could have been exploited to run arbitrary code. This vulnerability affects Firefox ESR < 128.11.
Ubuntu
Thunderbird vulnerabilities
vendor_ubuntu·2025-07-22
CVE-2025-4083 Thunderbird vulnerabilities
Title: Thunderbird vulnerabilities
Summary: Several security issues were fixed in Thunderbird.
Multiple security issues were discovered in Thunderbird. If a user were
tricked into opening a specially crafted website in a browsing context, an
attacker could potentially exploit these to cause a denial of service,
obtain sensitive information, bypass security restrictions, cross-site
tracing, or execute arbitrary code.
Instructions: This update uses a new upstream release, which includes additional bug
fixes. After a standard system update you need to restart thunderbird to
make all the necessary changes.
Red Hat
firefox: thunderbird: Memory safety bug
vendor_redhat·2025-05-27·CVSS 8.1
CVE-2025-5269 [HIGH] CWE-119 firefox: thunderbird: Memory safety bug
firefox: thunderbird: Memory safety bug
Memory safety bug present in Firefox ESR 128.10, and Thunderbird 128.10. This bug showed evidence of memory corruption and we presume that with enough effort this could have been exploited to run arbitrary code. This vulnerability affects Firefox ESR < 128.11 and Thunderbird < 128.11.
A flaw was found in Firefox. The Mozilla Foundation's Security Advisory describes the following issue: This bug shows evidence of memory corruption and we presume that with enough effort this could be exploited to run arbitrary code.
Statement: Red Hat Product Security rates the severity of this flaw as determined by the Mozilla Foundation Security Advisory.
Package: rhel10/firefox-flatpak (Red Hat Enterprise Linux 10) - Affected
Package: rhel10/thunderbird-flatpak
Debian
CVE-2025-5269: firefox-esr - Memory safety bug present in Firefox ESR 128.10, and Thunderbird 128.10. This bu...
vendor_debian·2025·CVSS 8.1
CVE-2025-5269 [HIGH] CVE-2025-5269: firefox-esr - Memory safety bug present in Firefox ESR 128.10, and Thunderbird 128.10. This bu...
Memory safety bug present in Firefox ESR 128.10, and Thunderbird 128.10. This bug showed evidence of memory corruption and we presume that with enough effort this could have been exploited to run arbitrary code. This vulnerability affects Firefox ESR < 128.11 and Thunderbird < 128.11.
Scope: local
bookworm: resolved (fixed in 128.11.0esr-1~deb12u1)
bullseye: resolved (fixed in 128.11.0esr-1~deb11u1)
forky: resolved (fixed in 128.11.0esr-1)
sid: resolved (fixed in 128.11.0esr-1)
trixie: resolved (fixed in 128.11.0esr-1)
Mozilla
Mozilla Foundation Security Advisory 2025-44: CVE-2025-5269
vendor_mozilla·CVSS 8.1
CVE-2025-5269 [HIGH] Mozilla Foundation Security Advisory 2025-44: CVE-2025-5269
Mozilla Foundation Security Advisory 2025-44
CVE: CVE-2025-5269
Product: Firefox ESR
Impact: moderate
Fixed in: Firefox ESR 128.11
Mozilla
Mozilla Foundation Security Advisory 2025-46: CVE-2025-5269
vendor_mozilla·CVSS 8.1
CVE-2025-5269 [HIGH] Mozilla Foundation Security Advisory 2025-46: CVE-2025-5269
Mozilla Foundation Security Advisory 2025-46
CVE: CVE-2025-5269
Product: Thunderbird
Impact: moderate
Fixed in: Thunderbird 128.11
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
2025-05-27
Published