CVE-2025-13012VulnerabilityPublished 13 Nov 2025Updated 28 Jun 2026

Red Hat Security Advisory: firefox security update

Affects Red Hat firefoxSource GCVE Database

Mentioned vulnerabilities

CVE-2025-13020

Authoritative record:CVE-2025-13012· High 7.5

Not known to be exploited · CVSS 7.5 High.

Data as of 26 Oct 2026, 09:15 UTC

CVSS 3.1 base score

7.5High

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

EPSS: 0.2% chance of exploitation in 30 days – higher than 15% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

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

Exploitation evidence

Disclosed: evidence found.
CVE published 11 Nov 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 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

AI-suggested

Red Hat has released updated Firefox packages for Red Hat Enterprise Linux 9 that address these vulnerabilities. Users should apply the security update as detailed in the Red Hat advisory RHSA-2025:21280 and the referenced article https://access.redhat.com/articles/11258 to remediate these issues. Since this is an official fix, applying the update is the recommended mitigation. No additional vendor guidance indicates other mitigations or that no action is required.

Description

Multiple security vulnerabilities have been identified and addressed in Mozilla Firefox as packaged for Red Hat Enterprise Linux 9. These include issues such as race conditions, use-after-free bugs, same-origin policy bypasses, mitigation bypasses, and spoofing vulnerabilities affecting various components like DOM, Audio/Video, WebAssembly, WebRTC, and Graphics. The update is rated as Important by Red Hat Product Security and addresses nine CVEs. Users of affected Red Hat Enterprise Linux 9 variants are advised to apply the provided Firefox update to remediate these issues.

Impact

The vulnerabilities impact the security of Firefox by potentially allowing bypasses of security mitigations, use-after-free conditions that could lead to memory corruption, same-origin policy bypasses that could allow unauthorized access to web content, race conditions that could cause unpredictable behavior, and spoofing that could mislead users. These issues collectively pose a high security risk to users running affected Firefox versions on Red Hat Enterprise Linux 9, potentially enabling attackers to compromise browser security and user data.

CWE-366Race Condition within a Thread (opens in a new tab)
Base weaknessLikelihood of exploit: Medium
If two threads of execution use a resource simultaneously, there exists the possibility that resources may be used while invalid, in turn making the state of execution undefined.
Architecture and Design
Use locking functionality. This is the recommended solution. Implement some form of locking mechanism around code which alters or reads persistent data in a multithreaded environment.
Architecture and Design
Create resource-locking validation checks. If no inherent locking mechanisms exist, use flags and signals to enforce your own blocking scheme when resources are being used by other threads of execution.
OWASP Cheat Sheets
Abuse Case (opens in a new tab)
OWASP ASVS 4.0.3
V1.11.2 (opens in a new tab)
Attack patterns
Leveraging Time-of-Check and Time-of-Use (TOCTOU) Race Conditions (opens in a new tab)
Leveraging Race Conditions (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).
CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') (opens in a new tab)
Base weaknessLikelihood of exploit: HighCWE Top 25 (2025): #1OWASP Top 10 A05:2025: Injection (opens in a new tab)
The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.
Architecture and Design · Libraries or Frameworks
Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.
Implementation · Architecture and Design
Understand the context in which your data will be used and the encoding that will be expected. This is especially important when transmitting data between different components, or when generating outputs that can contain multiple encodings at the same time, such as web pages or multi-part mail messages.
Architecture and Design · Implementation · Attack Surface Reduction
Understand all the potential areas where untrusted inputs can enter your software: parameters or arguments, cookies, anything read from the network, environment variables, reverse DNS lookups, query results, request headers, URL components, e-mail, files, filenames, databases, and any external systems that provide…
OWASP Cheat Sheets
Cross Site Scripting Prevention (opens in a new tab)
DOM based XSS Prevention (opens in a new tab)
Injection Prevention (opens in a new tab)
Abuse Case (opens in a new tab)
Deserialization (opens in a new tab)
OWASP ASVS 4.0.3
V5.3.3 (opens in a new tab)
V1.5.1 (opens in a new tab)
Attack patterns
XSS Using MIME Type Mismatch (opens in a new tab)
DOM-Based XSS (opens in a new tab)
Reflected XSS (opens in a new tab)
Stored XSS (opens in a new tab)
Cross-Site Scripting (XSS) (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).
CWE-825Expired Pointer Dereference (opens in a new tab)
Base weakness
The product dereferences a pointer that contains a location for memory that was previously valid, but is no longer valid.
Architecture and Design
Choose a language that provides automatic memory management.
Implementation
When freeing pointers, be sure to set them to NULL once they are freed. However, the utilization of multiple or complex data structures may lower the usefulness of this strategy.
OWASP Cheat Sheets
XML Security (opens in a new tab)
Mass Assignment (opens in a new tab)
OWASP ASVS 4.0.3
V13.3.1 (opens in a new tab)
V5.1.4 (opens in a new tab)
V5.1.3 (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).
CWE-290Authentication Bypass by Spoofing (opens in a new tab)
Base weaknessOWASP Top 10 A07:2025: Authentication Failures (opens in a new tab)
This attack-focused weakness is caused by incorrectly implemented authentication schemes that are subject to spoofing attacks.
OWASP Cheat Sheets
REST Security (opens in a new tab)
JSON Web Token for Java (opens in a new tab)
OWASP Authentication (opens in a new tab)
OWASP ASVS 4.0.3
V3.5.1 (opens in a new tab)
V2.8.5 (opens in a new tab)
V2.8.4 (opens in a new tab)
Attack patterns
Creating a Rogue Certification Authority Certificate (opens in a new tab)
Web Services API Signature Forgery Leveraging Hash Function Extension Weakness (opens in a new tab)
Signature Spoof (opens in a new tab)
Signature Spoofing by Misrepresentation (opens in a new tab)
Session Credential Falsification through Prediction (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).
CWE-787Out-of-bounds Write (opens in a new tab)
Base weaknessLikelihood of exploit: HighCWE Top 25 (2025): #5
The product writes data past the end, or before the beginning, of the intended buffer.
Requirements · Language Selection
Use a language that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.
Architecture and Design · Libraries or Frameworks
Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.
Operation · Build and Compilation · Environment Hardening
Use automatic buffer overflow detection mechanisms that are offered by certain compilers or compiler extensions. Examples include: the Microsoft Visual Studio /GS flag, Fedora/Red Hat FORTIFY_SOURCE GCC flag, StackGuard, and ProPolice, which provide various mechanisms including canary-based detection and range/index…
OWASP Cheat Sheets
XML Security (opens in a new tab)
Mass Assignment (opens in a new tab)
OWASP ASVS 4.0.3
V13.3.1 (opens in a new tab)
V5.1.4 (opens in a new tab)
V5.1.3 (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).
CWE-501Trust Boundary Violation (opens in a new tab)
Base weaknessOWASP Top 10 A06:2025: Insecure Design (opens in a new tab)
The product mixes trusted and untrusted data in the same data structure or structured message.
OWASP Cheat Sheets
Secure Design Principles (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).
CWE-346Origin Validation Error (opens in a new tab)
Class weaknessOWASP Top 10 A07:2025: Authentication Failures (opens in a new tab)
The product does not properly verify that the source of data or communication is valid.
OWASP Cheat Sheets
OWASP Authentication (opens in a new tab)
OWASP ASVS 4.0.3
V14.5.2 (opens in a new tab)
V14.5.3 (opens in a new tab)
V1.4.4 (opens in a new tab)
Attack patterns
JSON Hijacking (aka JavaScript Hijacking) (opens in a new tab)
Cache Poisoning (opens in a new tab)
DNS Cache Poisoning (opens in a new tab)
Exploit Script-Based APIs (opens in a new tab)
Application API Message Manipulation via Man-in-the-Middle (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

Description

AI analysisMachine-generated, updated 28 Jun 2026, 22:20 UTC

WeaknessesCWE-366, CWE-79, CWE-825 +4

Technical details

References

Community reviews

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