VulnerabilityPublished 19 Aug 2025Updated 13 Apr 2026

CVE-2025-8364: Mozilla Firefox · CWE-451

Affects Mozilla FirefoxSource CVE Database V5

Not known to be exploited · CVSS 4.3 Medium : upgrade to 141 when convenient.

Data as of 26 Oct 2026, 10:12 UTC

CVSS 3.1 base score

4.3Medium

How severe the flaw is on the 0–10 CVSS scale.

EPSS: 0.2% chance of exploitation in 30 days – higher than 13% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in 141

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N

Attack Vector: Network
Attack Complexity: Low
Privileges Required: None
User Interaction: Required
Scope: Unchanged
Confidentiality: None
Integrity: Low
Availability: None

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Network: The vulnerable component is bound to the network stack and the set of possible attackers extends beyond the other options listed, up to and including the entire Internet. Such a vulnerability is often termed 'remotely exploitable' and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers).
Attack Complexity: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
Privileges Required: None: The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files to carry out an attack.
User Interaction: Required: Successful exploitation of this vulnerability requires a user to take some action before the vulnerability can be exploited.
Scope: Unchanged: An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.
Confidentiality: None: There is no loss of confidentiality within the impacted component.
Integrity: Low: Modification of data is possible, but the attacker does not have control over the consequence of a modification, or the amount of modification is limited. The data modification does not have a direct, serious impact on the impacted component.
Availability: None: There is no impact to availability within the impacted component.

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 19 Aug 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: 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 26 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Upgrade Mozilla Firefox to 141.

Affected software

Product	Affected	Fixed in
Mozilla Firefox	Affected <141	Fixed in 141

AI-suggested

This vulnerability has been fixed in Firefox 141. Users and administrators should update Firefox on Android devices to version 141 or later to remediate this issue. No additional mitigation actions are required as the vendor has provided an official fix.

Description

A crafted URL using a blob: URI could have hidden the true origin of the page, resulting in a potential spoofing attack. *Note: This issue only affected Android operating systems. Other operating systems are unaffected.*. This vulnerability was fixed in Firefox 141.

Impact

The vulnerability could allow an attacker to craft a URL that hides the true origin of a page in Firefox for Android, potentially misleading users and enabling spoofing attacks. There is no direct confidentiality or availability impact reported. The issue is limited to Android devices running affected versions of Firefox prior to 141. Other operating systems are not affected.

Summary

This vulnerability involves Firefox for Android incorrectly handling blob: URIs in the address bar, allowing the displayed URL to hide the actual origin of the page. This could mislead users about the legitimacy of the site they are visiting, constituting a potential spoofing attack. The issue is specific to the Android platform and was resolved in Firefox 141. The CVSS vector indicates network attack vector, low attack complexity, no privileges required, user interaction required, unchanged scope, no confidentiality or availability impact, and low integrity impact.

CWE-451User Interface (UI) Misrepresentation of Critical Information (opens in a new tab)
Class weaknessOWASP Top 10 A06:2025: Insecure Design (opens in a new tab)
The user interface (UI) does not properly represent critical information to the user, allowing the information - or its source - to be obscured or spoofed. This is often a component in phishing attacks.
Implementation · Input Validation
Perform data validation (e.g. syntax, length, etc.) before interpreting the data.
Architecture and Design · Output Encoding
Create a strategy for presenting information, and plan for how to display unusual characters.
OWASP Cheat Sheets
Secure Design Principles (opens in a new tab)
Attack patterns
Spear Phishing (opens in a new tab)
Mobile Phishing (opens in a new tab)
Phishing (opens in a new tab)
Resource Location Spoofing (opens in a new tab)
Action Spoofing (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 14 Apr 2026, 11:55 UTC

WeaknessesCWE-451

Technical details

References

Community reviews

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