CVE-2025-5266
published 2025-05-27CVE-2025-5266: Script elements loading cross-origin resources generated load and error events which leaked information enabling XS-Leaks attacks. This vulnerability was fixed…
PriorityP417medium4.3CVSS 3.1
AVNACLPRNUIRSUCLINAN
EPSS
0.27%
19.5th percentile
Script elements loading cross-origin resources generated load and error events which leaked information enabling XS-Leaks attacks. This vulnerability was fixed in Firefox 139, Firefox ESR 128.11, Thunderbird 139, and Thunderbird 128.11.
Affected
10 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | firefox | < firefox 139.0-1 (sid) | firefox 139.0-1 (sid) |
| debian | firefox-esr | < firefox 139.0-1 (sid) | firefox 139.0-1 (sid) |
| debian | thunderbird | < firefox 139.0-1 (sid) | firefox 139.0-1 (sid) |
| mozilla | firefox | < 128.11.0 | 128.11.0 |
| mozilla | firefox | < 139.0 | 139.0 |
| mozilla | firefox | — | — |
| 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
nvdv3.14.3MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N
osv4.3MEDIUM
vendor_debian4.3MEDIUM
vendor_redhat4.3MEDIUM
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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: Script element events leaked cross-origin resource status
vendor_redhat·2025-05-27·CVSS 4.3
CVE-2025-5266 [MEDIUM] CWE-829 firefox: thunderbird: Script element events leaked cross-origin resource status
firefox: thunderbird: Script element events leaked cross-origin resource status
Script elements loading cross-origin resources generated load and error events which leaked information enabling XS-Leaks attacks. This vulnerability affects Firefox < 139, Firefox ESR < 128.11, Thunderbird < 139, and Thunderbird < 128.11.
A flaw was found in Firefox. The Mozilla Foundation's Security Advisory describes the following issue: Script elements loading cross-origin resources generate load and error events which can leak information enabling XS-Leaks attacks.
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 (Red
Debian
CVE-2025-5266: firefox - Script elements loading cross-origin resources generated load and error events w...
vendor_debian·2025·CVSS 4.3
CVE-2025-5266 [MEDIUM] CVE-2025-5266: firefox - Script elements loading cross-origin resources generated load and error events w...
Script elements loading cross-origin resources generated load and error events which leaked information enabling XS-Leaks attacks. This vulnerability affects Firefox < 139, Firefox ESR < 128.11, Thunderbird < 139, and Thunderbird < 128.11.
Scope: local
sid: resolved (fixed in 139.0-1)
Mozilla
Mozilla Foundation Security Advisory 2025-44: CVE-2025-5266
vendor_mozilla·CVSS 4.3
CVE-2025-5266 [MEDIUM] Mozilla Foundation Security Advisory 2025-44: CVE-2025-5266
Mozilla Foundation Security Advisory 2025-44
CVE: CVE-2025-5266
Product: Firefox ESR
Impact: moderate
Fixed in: Firefox ESR 128.11
Mozilla
Mozilla Foundation Security Advisory 2025-42: CVE-2025-5266
vendor_mozilla·CVSS 4.3
CVE-2025-5266 [MEDIUM] Mozilla Foundation Security Advisory 2025-42: CVE-2025-5266
Mozilla Foundation Security Advisory 2025-42
CVE: CVE-2025-5266
Product: Firefox
Impact: moderate
Fixed in: Firefox 139
Mozilla
Mozilla Foundation Security Advisory 2025-45: CVE-2025-5266
vendor_mozilla·CVSS 4.3
CVE-2025-5266 [MEDIUM] Mozilla Foundation Security Advisory 2025-45: CVE-2025-5266
Mozilla Foundation Security Advisory 2025-45
CVE: CVE-2025-5266
Product: Thunderbird
Impact: moderate
Fixed in: Thunderbird 139
Mozilla
Mozilla Foundation Security Advisory 2025-46: CVE-2025-5266
vendor_mozilla·CVSS 4.3
CVE-2025-5266 [MEDIUM] Mozilla Foundation Security Advisory 2025-46: CVE-2025-5266
Mozilla Foundation Security Advisory 2025-46
CVE: CVE-2025-5266
Product: Thunderbird
Impact: moderate
Fixed in: Thunderbird 128.11
OSV
CVE-2025-5266: Script elements loading cross-origin resources generated load and error events which leaked information enabling XS-Leaks attacks
osv·2025-05-27·CVSS 4.3
CVE-2025-5266 [MEDIUM] CVE-2025-5266: Script elements loading cross-origin resources generated load and error events which leaked information enabling XS-Leaks attacks
Script elements loading cross-origin resources generated load and error events which leaked information enabling XS-Leaks attacks. This vulnerability affects Firefox < 139, Firefox ESR < 128.11, Thunderbird < 139, and Thunderbird < 128.11.
GHSA
GHSA-xv7q-j96c-5r6v: Script elements loading cross-origin resources generated load and error events which leaked information enabling XS-Leaks attacks
ghsa_unreviewed·2025-05-27
CVE-2025-5266 [MEDIUM] CWE-200 GHSA-xv7q-j96c-5r6v: Script elements loading cross-origin resources generated load and error events which leaked information enabling XS-Leaks attacks
Script elements loading cross-origin resources generated load and error events which leaked information enabling XS-Leaks attacks. This vulnerability affects Firefox < 139 and Firefox ESR < 128.11.
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
https://bugzilla.mozilla.org/show_bug.cgi?id=1965628https://www.mozilla.org/security/advisories/mfsa2025-42/https://www.mozilla.org/security/advisories/mfsa2025-44/https://www.mozilla.org/security/advisories/mfsa2025-45/https://www.mozilla.org/security/advisories/mfsa2025-46/https://lists.debian.org/debian-lts-announce/2025/05/msg00043.htmlhttps://lists.debian.org/debian-lts-announce/2025/05/msg00046.html
2025-05-27
Published