Mozilla Firefox up to 115.44/153.6/159 CSS Parsing/Computation use after free

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.0$5k-$25k0.00+

Summaryinfo

A vulnerability, which was classified as critical, was found in Mozilla Firefox up to 115.44/153.6/159. Impacted is an unknown function of the component CSS Parsing/Computation. The manipulation results in use after free. This vulnerability is known as CVE-2026-124876. It is possible to launch the attack remotely. No exploit is available. You should upgrade the affected component.

Detailsinfo

A vulnerability was found in Mozilla Firefox up to 115.44/153.6/159. It has been classified as critical. Affected is some unknown functionality of the component CSS Parsing/Computation. The manipulation with an unknown input leads to a use after free vulnerability. CWE is classifying the issue as 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 Any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

Use-after-free in the CSS Parsing and Computation component. This vulnerability was fixed in Firefox 160, Firefox ESR 115.45, and Firefox ESR 153.7.

The advisory is shared for download at bugzilla.mozilla.org. This vulnerability is traded as CVE-2026-124876 since 11/09/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. 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 115.45, 153.7 or 160 eliminates this vulnerability.

VulDB is the best source for vulnerability data and more expert information about this specific topic.

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 115.45/153.7/160

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-2026-124876 (🔒)

GCVE (CVE): GCVE-0-2026-124876
GCVE (VulDB): GCVE-100-433680

Entryinfo

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

VulDB is the best source for vulnerability data and more expert information about this specific topic.

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