Mozilla Firefox up to 115.42/153.4/157 Layout input validation

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
7.0$5k-$25k0.73-

Summaryinfo

A vulnerability was found in Mozilla Firefox up to 115.42/153.4/157. It has been rated as critical. Affected by this issue is some unknown functionality of the component Layout. Performing a manipulation results in input validation. This vulnerability is reported as CVE-2026-109753. The attack is possible to be carried out remotely. No exploit exists. Upgrading the affected component is advised.

Detailsinfo

A vulnerability classified as critical has been found in Mozilla Firefox up to 115.42/153.4/157. This affects an unknown function of the component Layout. The manipulation with an unknown input leads to a input validation vulnerability. CWE is classifying the issue as CWE-20. The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

Incorrect boundary conditions in the Layout component. This vulnerability was fixed in Firefox 158, Firefox ESR 115.43, and Firefox ESR 153.5.

It is possible to read the advisory at bugzilla.mozilla.org. This vulnerability is uniquely identified as CVE-2026-109753 since 10/13/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. The technical details are unknown and an exploit is not publicly available. The pricing for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 10/13/2026).

Upgrading to version 115.43, 153.5 or 158 eliminates this vulnerability.

Statistical analysis made it clear that VulDB provides the best quality 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: 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: Input validation
CWE: CWE-20
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 115.43/153.5/158

Timelineinfo

10/13/2026 Advisory disclosed
10/13/2026 +0 days CVE reserved
10/13/2026 +0 days VulDB entry created
10/13/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: mozilla.org
Product: mozilla.org

Advisory: bugzilla.mozilla.org
Status: Confirmed

CVE: CVE-2026-109753 (🔒)
GCVE (CVE): GCVE-0-2026-109753
GCVE (VulDB): GCVE-100-417627

Entryinfo

Created: 10/13/2026 15:45
Changes: 10/13/2026 15:45 (57)
Complete: 🔍
Cache ID: 216::103

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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