CVE-2025-8031: The username:password part was not correctly stripped from URLs in CSP reports potentially leaking
Source GCVE Database
Not known to be exploited · CVSS 9.8 Critical · fixed in 141 : patch affected systems as a priority.
Data as of 30 Oct 2026, 01:49 UTC
- Patch
- Available – fixed in 141, 140.1, 128.13
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 22 Jul 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 29 Oct 2026.
What to do
AI-suggested
Mozilla has fixed this vulnerability in Firefox 141 and Thunderbird 141. Users and administrators should update to these versions or later to mitigate the risk. No additional mitigation steps are required beyond applying the official patches.
Description
CVE-2025-8031 is a vulnerability in Firefox and Thunderbird where the username:password portion of URLs was not properly stripped from Content Security Policy (CSP) reports. This flaw could lead to the unintended leakage of HTTP Basic Authentication credentials. The issue affects versions of Firefox prior to 141 and Thunderbird prior to 141, including certain ESR versions. Mozilla has addressed this vulnerability in Firefox 141 and Thunderbird 141.
References
- nvd.nist.gov/vuln/detail/CVE-2025-8031 (opens in a new tab)
- bugzilla.mozilla.org/show_bug.cgi?id=1971719 (opens in a new tab)
- lists.debian.org/debian-lts-announce/2025/07/msg00016.html (opens in a new tab)
- mozilla.org/security/advisories/mfsa2025-56 (opens in a new tab)
- mozilla.org/security/advisories/mfsa2025-58 (opens in a new tab)
- mozilla.org/security/advisories/mfsa2025-59 (opens in a new tab)
- mozilla.org/security/advisories/mfsa2025-61 (opens in a new tab)
- mozilla.org/security/advisories/mfsa2025-62 (opens in a new tab)
- mozilla.org/security/advisories/mfsa2025-63 (opens in a new tab)