Mozilla Firefox up to 140.13/153/153.0 JIT memory corruption

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 was found in Mozilla Firefox up to 140.13/153/153.0 and classified as critical. This issue affects some unknown processing of the component JIT. The manipulation results in memory corruption. This vulnerability is identified as CVE-2026-74976. The attack can be executed remotely. There is not any exploit available.

Detailsinfo

A vulnerability classified as critical has been found in Mozilla Firefox up to 140.13/153/153.0. Affected is an unknown code of the component JIT. The manipulation with an unknown input leads to a memory corruption vulnerability. CWE is classifying the issue as CWE-119. The product performs operations on a memory buffer, but it can read from or write to a memory location that is outside of the intended boundary of the buffer. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

JIT miscompilation in the JavaScript Engine: JIT component. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, and Firefox ESR 153.1.

The advisory is available at bugzilla.mozilla.org. This vulnerability is traded as CVE-2026-74976 since 08/17/2026. 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. The technical details are unknown and an exploit is not available. The structure of the vulnerability defines a possible price range of USD $5k-$25k at the moment (estimation calculated on 08/18/2026).

Upgrading to version 140.14, 153.1 or 154 eliminates this vulnerability.

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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: Memory corruption
CWE: 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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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Firefox 140.14/153.1/154

Timelineinfo

08/17/2026 CVE reserved
08/18/2026 +1 days Advisory disclosed
08/18/2026 +0 days VulDB entry created
08/18/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: mozilla.org
Product: mozilla.org

Advisory: bugzilla.mozilla.org
Status: Confirmed

CVE: CVE-2026-74976 (🔒)
GCVE (CVE): GCVE-0-2026-74976
GCVE (VulDB): GCVE-100-391626

Entryinfo

Created: 08/18/2026 15:28
Changes: 08/18/2026 15:28 (57)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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