Mozilla Firefox up to 153.6/159 Layout array index

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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7.0$5k-$25k0.00+

Summaryinfo

A vulnerability identified as critical has been detected in Mozilla Firefox up to 153.6/159. Impacted is an unknown function of the component Layout. The manipulation leads to array index. This vulnerability is uniquely identified as CVE-2026-124887. The attack is possible to be carried out remotely. No exploit exists. You should upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as critical, has been found in Mozilla Firefox up to 153.6/159. This issue affects some unknown functionality of the component Layout. The manipulation with an unknown input leads to a array index vulnerability. Using CWE to declare the problem leads to CWE-129. The product uses untrusted input when calculating or using an array index, but the product does not validate or incorrectly validates the index to ensure the index references a valid position within the array. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

Incorrect boundary conditions in the Layout: Text and Fonts component. This vulnerability was fixed in Firefox 160 and Firefox ESR 153.7.

The advisory is shared at bugzilla.mozilla.org. The identification of this vulnerability is CVE-2026-124887 since 11/09/2026. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. Neither technical details nor an exploit are publicly available. The price for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 11/10/2026).

Upgrading to version 153.7 or 160 eliminates this vulnerability.

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.3
VulDB Meta Temp Score: 7.0

VulDB Base Score: 7.3
VulDB Temp Score: 7.0
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: Array index
CWE: CWE-129 / 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-2026-124887 (🔒)

GCVE (CVE): GCVE-0-2026-124887
GCVE (VulDB): GCVE-100-433757

Entryinfo

Created: 11/10/2026 15:41
Changes: 11/10/2026 15:41 (57)
Complete: 🔍
Cache ID: 216::103

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