Mozilla Firefox up to 115.41/140.16/153.3/156 DOM Content Processes 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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7.0$5k-$25k0.00

Summaryinfo

A vulnerability has been found in Mozilla Firefox up to 115.41/140.16/153.3/156 and classified as critical. Affected by this vulnerability is an unknown functionality of the component DOM Content Processes. The manipulation leads to use after free. This vulnerability is listed as CVE-2026-100762. The attack may be initiated remotely. There is no available exploit. The affected component should be upgraded.

Detailsinfo

A vulnerability was found in Mozilla Firefox up to 115.41/140.16/153.3/156 and classified as critical. This issue affects an unknown part of the component DOM Content Processes. The manipulation with an unknown input leads to a use after free vulnerability. Using CWE to declare the problem leads to CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

Sandbox escape due to use-after-free in the DOM: Content Processes component. This vulnerability was fixed in Firefox ESR 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17.

It is possible to read the advisory at bugzilla.mozilla.org. The identification of this vulnerability is CVE-2026-100762 since 09/26/2026. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful 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 10/01/2026).

The vulnerability scanner Nessus provides a plugin with the ID 351382 (Linux Distros Unpatched Vulnerability : CVE-2026-100762), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 115.42, 140.17, 153.4 or 157 eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (351382) and CERT Bund (WID-SEC-2026-3654). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Affected

  • Debian Linux
  • Mozilla Firefox ESR
  • Mozilla Firefox
  • Mozilla Thunderbird

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

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 351382
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2026-100762

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Firefox 115.42/140.17/153.4/157

Timelineinfo

09/26/2026 CVE reserved
09/29/2026 +3 days Advisory disclosed
09/29/2026 +0 days VulDB entry created
10/01/2026 +2 days VulDB entry last update

Sourcesinfo

Vendor: mozilla.org
Product: mozilla.org

Advisory: bugzilla.mozilla.org
Status: Confirmed

CNA: mozilla
CVE: CVE-2026-100762 (🔒)

GCVE (CVE): GCVE-0-2026-100762
GCVE (VulDB): GCVE-100-411323
CERT Bund: WID-SEC-2026-3654 - Mozilla Firefox, Firefox ESR und Thunderbird: Mehrere Schwachstellen

Entryinfo

Created: 09/29/2026 15:05
Updated: 10/01/2026 12:02
Changes: 09/29/2026 15:05 (57), 09/30/2026 13:08 (2), 10/01/2026 12:02 (7)
Complete: 🔍
Cache ID: 216::103

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

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