CVE-2025-5271
published 2025-05-27CVE-2025-5271: Previewing a response in Devtools ignored CSP headers, which could have allowed content injection attacks. This vulnerability was fixed in Firefox 139 and…
PriorityP431medium6.5CVSS 3.1
AVNACLPRNUINSUCLILAN
EPSS
0.26%
17.2th percentile
Previewing a response in Devtools ignored CSP headers, which could have allowed content injection attacks. This vulnerability was fixed in Firefox 139 and Thunderbird 139.
Affected
4 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | firefox | < firefox 139.0-1 (sid) | firefox 139.0-1 (sid) |
| mozilla | firefox | < 139.0 | 139.0 |
| mozilla | firefox | — | — |
| mozilla | thunderbird | >= 0 < 1:140.7.1+build1-0ubuntu0.22.04.1 | 1:140.7.1+build1-0ubuntu0.22.04.1 |
CVSS provenance
nvdv3.16.5MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
osv6.5MEDIUM
vendor_debian6.5MEDIUM
vendor_redhat6.5MEDIUM
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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.
Red Hat
firefox: Devtools' preview ignored CSP headers
vendor_redhat·2025-05-27·CVSS 6.5
CVE-2025-5271 [MEDIUM] CWE-807 firefox: Devtools' preview ignored CSP headers
firefox: Devtools' preview ignored CSP headers
Previewing a response in Devtools ignored CSP headers, which could have allowed content injection attacks. This vulnerability affects Firefox < 139 and Thunderbird < 139.
A flaw was found in Firefox. The Mozilla Foundation's Security Advisory describes the following issue: Previewing a response in Devtools ignors CSP headers, which could allow content injection attacks.
Statement: Red Hat Product Security rates the severity of this flaw as determined by the Mozilla Foundation Security Advisory.
Package: firefox (Red Hat Enterprise Linux 10) - Not affected
Package: rhel10/firefox-flatpak (Red Hat Enterprise Linux 10) - Not affected
Package: firefox (Red Hat Enterprise Linux 6) - Out of support scope
Package: firefox (Red Hat Enterprise L
Debian
CVE-2025-5271: firefox - Previewing a response in Devtools ignored CSP headers, which could have allowed ...
vendor_debian·2025·CVSS 6.5
CVE-2025-5271 [MEDIUM] CVE-2025-5271: firefox - Previewing a response in Devtools ignored CSP headers, which could have allowed ...
Previewing a response in Devtools ignored CSP headers, which could have allowed content injection attacks. This vulnerability affects Firefox < 139 and Thunderbird < 139.
Scope: local
sid: resolved (fixed in 139.0-1)
Mozilla
Mozilla Foundation Security Advisory 2025-42: CVE-2025-5271
vendor_mozilla·CVSS 6.5
CVE-2025-5271 [MEDIUM] Mozilla Foundation Security Advisory 2025-42: CVE-2025-5271
Mozilla Foundation Security Advisory 2025-42
CVE: CVE-2025-5271
Product: Firefox
Impact: moderate
Fixed in: Firefox 139
Mozilla
Mozilla Foundation Security Advisory 2025-45: CVE-2025-5271
vendor_mozilla·CVSS 6.5
CVE-2025-5271 [MEDIUM] Mozilla Foundation Security Advisory 2025-45: CVE-2025-5271
Mozilla Foundation Security Advisory 2025-45
CVE: CVE-2025-5271
Product: Thunderbird
Impact: moderate
Fixed in: Thunderbird 139
GHSA
GHSA-jc7v-r8h6-xr5c: Previewing a response in Devtools ignored CSP headers, which could have allowed content injection attacks
ghsa_unreviewed·2025-05-27
CVE-2025-5271 [MEDIUM] CWE-116 GHSA-jc7v-r8h6-xr5c: Previewing a response in Devtools ignored CSP headers, which could have allowed content injection attacks
Previewing a response in Devtools ignored CSP headers, which could have allowed content injection attacks. This vulnerability affects Firefox < 139.
OSV
CVE-2025-5271: Previewing a response in Devtools ignored CSP headers, which could have allowed content injection attacks
osv·2025-05-27·CVSS 6.5
CVE-2025-5271 [MEDIUM] CVE-2025-5271: Previewing a response in Devtools ignored CSP headers, which could have allowed content injection attacks
Previewing a response in Devtools ignored CSP headers, which could have allowed content injection attacks. This vulnerability affects Firefox < 139 and Thunderbird < 139.
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
2025-05-27
Published