CVE-2025-0243
published 2025-01-07CVE-2025-0243: 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…
PriorityP424medium5.1CVSS 3.1
AVLACLPRNUINSUCLILAN
EPSS
0.24%
15.9th percentile
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 was fixed in Firefox 134, Firefox ESR 128.6, Thunderbird 134, and Thunderbird 128.6.
Affected
13 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | firefox | < firefox 134.0-1 (sid) | firefox 134.0-1 (sid) |
| debian | firefox-esr | < firefox 134.0-1 (sid) | firefox 134.0-1 (sid) |
| debian | thunderbird | < firefox 134.0-1 (sid) | firefox 134.0-1 (sid) |
| mozilla | firefox | < 128.6.0 | 128.6.0 |
| mozilla | firefox | < 133.0 | 133.0 |
| mozilla | firefox | — | — |
| mozilla | firefox | >= 0 < 134.0+build1-0ubuntu0.20.04.1 | 134.0+build1-0ubuntu0.20.04.1 |
| mozilla | thunderbird | < 128.6.0 | 128.6.0 |
| mozilla | thunderbird | >= 0 < 1:128.6.0esr-1~deb11u1 | 1:128.6.0esr-1~deb11u1 |
| mozilla | thunderbird | >= 0 < 1:128.6.0esr-1~deb12u1 | 1:128.6.0esr-1~deb12u1 |
| mozilla | thunderbird | >= 0 < 1:128.6.0esr-1 | 1:128.6.0esr-1 |
| mozilla | thunderbird | >= 0 < 1:128.6.0esr-1 | 1:128.6.0esr-1 |
| mozilla | thunderbird | >= 129.0 < 134.0 | 134.0 |
CVSS provenance
nvdv3.15.1MEDIUMCVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
osv5.4MEDIUM
vendor_ubuntu5.4MEDIUM
vendor_debian5.1MEDIUM
vendor_redhat5.1MEDIUM
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Ubuntu
Thunderbird vulnerabilities
vendor_ubuntu·2026-02-02
CVE-2025-8031 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: In general, a standard system update will make all the necessary changes.
Ubuntu
Firefox vulnerabilities
vendor_ubuntu·2025-01-09·CVSS 5.4
CVE-2025-0240 [MEDIUM] Firefox vulnerabilities
Title: Firefox vulnerabilities
Summary: Several security issues were fixed in Firefox.
Multiple security issues were discovered in Firefox. If a user were
tricked into opening a specially crafted website, an attacker could
potentially exploit these to cause a denial of service, obtain sensitive
information across domains, or execute arbitrary code. (CVE-2025-0237,
CVE-2025-0239, CVE-2025-0240, CVE-2025-0242, CVE-2025-0243, CVE-2025-0247)
Irvan Kurniawan discovered that Firefox incorrectly handled memory when
breaking lines in text, leading to a use-after-free vulnerability. An
attacker could possibly use this issue to cause a denial of service or
possibly execute arbitrary code. (CVE-2025-0238)
Nils Bars discovered that Firefox incorrectly handled memory when using
JavaScript Text Segm
Red Hat
firefox: thunderbird: Memory safety bugs fixed in Firefox 134, Thunderbird 134, Firefox ESR 128.6, and Thunderbird 128.6
vendor_redhat·2025-01-07·CVSS 5.1
CVE-2025-0243 [MEDIUM] CWE-120 firefox: thunderbird: Memory safety bugs fixed in Firefox 134, Thunderbird 134, Firefox ESR 128.6, and Thunderbird 128.6
firefox: thunderbird: Memory safety bugs fixed in Firefox 134, Thunderbird 134, Firefox ESR 128.6, and Thunderbird 128.6
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, Firefox ESR < 128.6, Thunderbird < 134, and Thunderbird < 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 th
Debian
CVE-2025-0243: firefox - Memory safety bugs present in Firefox 133, Thunderbird 133, Firefox ESR 128.5, a...
vendor_debian·2025·CVSS 5.1
CVE-2025-0243 [MEDIUM] CVE-2025-0243: firefox - Memory safety bugs present in Firefox 133, Thunderbird 133, Firefox ESR 128.5, a...
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, Firefox ESR < 128.6, Thunderbird < 134, and Thunderbird < 128.6.
Scope: local
sid: resolved (fixed in 134.0-1)
Mozilla
Mozilla Foundation Security Advisory 2025-05: CVE-2025-0243
vendor_mozilla·CVSS 5.1
CVE-2025-0243 [MEDIUM] Mozilla Foundation Security Advisory 2025-05: CVE-2025-0243
Mozilla Foundation Security Advisory 2025-05
CVE: CVE-2025-0243
Product: Thunderbird
Impact: moderate
Fixed in: Thunderbird 128.6
Mozilla
Mozilla Foundation Security Advisory 2025-04: CVE-2025-0243
vendor_mozilla·CVSS 5.1
CVE-2025-0243 [MEDIUM] Mozilla Foundation Security Advisory 2025-04: CVE-2025-0243
Mozilla Foundation Security Advisory 2025-04
CVE: CVE-2025-0243
Product: Thunderbird
Impact: high
Fixed in: Thunderbird 134
Mozilla
Mozilla Foundation Security Advisory 2025-01: CVE-2025-0243
vendor_mozilla·CVSS 5.1
CVE-2025-0243 [MEDIUM] Mozilla Foundation Security Advisory 2025-01: CVE-2025-0243
Mozilla Foundation Security Advisory 2025-01
CVE: CVE-2025-0243
Product: Firefox
Impact: high
Fixed in: Firefox 134
Mozilla
Mozilla Foundation Security Advisory 2025-02: CVE-2025-0243
vendor_mozilla·CVSS 5.1
CVE-2025-0243 [MEDIUM] Mozilla Foundation Security Advisory 2025-02: CVE-2025-0243
Mozilla Foundation Security Advisory 2025-02
CVE: CVE-2025-0243
Product: Firefox ESR
Impact: moderate
Fixed in: Firefox ESR 128.6
OSV
firefox vulnerabilities
osv·2025-01-09·CVSS 5.4
CVE-2025-0237 [MEDIUM] firefox vulnerabilities
firefox vulnerabilities
Multiple security issues were discovered in Firefox. If a user were
tricked into opening a specially crafted website, an attacker could
potentially exploit these to cause a denial of service, obtain sensitive
information across domains, or execute arbitrary code. (CVE-2025-0237,
CVE-2025-0239, CVE-2025-0240, CVE-2025-0242, CVE-2025-0243, CVE-2025-0247)
Irvan Kurniawan discovered that Firefox incorrectly handled memory when
breaking lines in text, leading to a use-after-free vulnerability. An
attacker could possibly use this issue to cause a denial of service or
possibly execute arbitrary code. (CVE-2025-0238)
Nils Bars discovered that Firefox incorrectly handled memory when using
JavaScript Text Segmentation. An attacker could possibly use this issue to
cause a d
GHSA
GHSA-928f-3rxq-5jvp: Memory safety bugs present in Firefox 133, Thunderbird 133, Firefox ESR 128
ghsa_unreviewed·2025-01-07
CVE-2025-0243 [MEDIUM] CWE-787 GHSA-928f-3rxq-5jvp: Memory safety bugs present in Firefox 133, Thunderbird 133, Firefox ESR 128
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.
OSV
CVE-2025-0243: Memory safety bugs present in Firefox 133, Thunderbird 133, Firefox ESR 128
osv·2025-01-07·CVSS 5.1
CVE-2025-0243 [MEDIUM] CVE-2025-0243: Memory safety bugs present in Firefox 133, Thunderbird 133, Firefox ESR 128
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, Firefox ESR < 128.6, Thunderbird < 134, and Thunderbird < 128.6.
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
https://bugzilla.mozilla.org/buglist.cgi?bug_id=1827142%2C1932783https://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/https://lists.debian.org/debian-lts-announce/2025/01/msg00004.html
2025-01-07
Published