Mozilla Firefox up to 153.6/159 Core/HTML use after free

CVSS Meta Temp Score
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CTI Interest Score
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6.0$5k-$25k0.00+

Summaryinfo

A vulnerability described as critical has been identified in Mozilla Firefox up to 153.6/159. Affected by this issue is some unknown functionality of the component Core/HTML Component. Such manipulation leads to use after free. This vulnerability is documented as CVE-2026-124869. The attack can be executed remotely. There is not any exploit available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability, which was classified as critical, has been found in Mozilla Firefox up to 153.6/159. Affected by this issue is an unknown code block of the component Core/HTML Component. The manipulation with an unknown input leads to a use after free vulnerability. Using CWE to declare the problem leads to CWE-416. The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer. Impacted is confidentiality, integrity, and availability. CVE summarizes:

Use-after-free in the DOM: Core & HTML component. This vulnerability was fixed in Firefox 160 and Firefox ESR 153.7.

The advisory is shared for download at bugzilla.mozilla.org. This vulnerability is handled as CVE-2026-124869 since 11/09/2026. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. Successful exploitation requires user interaction by the victim. There are neither technical details nor an exploit publicly available. The current price for an exploit might be approx. USD $5k-$25k (estimation calculated on 11/10/2026).

Upgrading to version 153.7 or 160 eliminates this vulnerability.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.3
VulDB Meta Temp Score: 6.0

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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💳💳💳💳💳💳
💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Use after free
CWE: CWE-416 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Firefox 153.7/160

Timelineinfo

11/09/2026 CVE reserved
11/10/2026 +1 days Advisory disclosed
11/10/2026 +0 days VulDB entry created
11/10/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: mozilla.org
Product: mozilla.org

Advisory: bugzilla.mozilla.org
Status: Confirmed

CNA: mozilla
CVE: CVE-2026-124869 (🔒)

GCVE (CVE): GCVE-0-2026-124869
GCVE (VulDB): GCVE-100-433676

Entryinfo

Created: 11/10/2026 14:57
Changes: 11/10/2026 14:57 (57)
Complete: 🔍
Cache ID: 216::103

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