Mozilla Firefox up to 148 XPCOM integer overflow

CVSS Meta Temp Score
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CTI Interest Score
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8.7$5k-$25k0.00

Summaryinfo

A vulnerability was found in Mozilla Firefox up to 148. It has been declared as critical. Affected is an unknown function of the component XPCOM. Such manipulation leads to integer overflow. This vulnerability is documented as CVE-2026-4689. The attack can be executed remotely. There is not any exploit available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability was found in Mozilla Firefox up to 148. It has been rated as critical. Affected by this issue is some unknown processing of the component XPCOM. The manipulation with an unknown input leads to a integer overflow vulnerability. Using CWE to declare the problem leads to CWE-190. The product performs a calculation that can produce an integer overflow or wraparound, when the logic assumes that the resulting value will always be larger than the original value. This can introduce other weaknesses when the calculation is used for resource management or execution control. Impacted is confidentiality, integrity, and availability. CVE summarizes:

Sandbox escape due to incorrect boundary conditions, integer overflow in the XPCOM component. This vulnerability was fixed in Firefox 149, Firefox ESR 115.34, Firefox ESR 140.9, Thunderbird 149, and Thunderbird 140.9.

The advisory is shared for download at bugzilla.mozilla.org. This vulnerability is handled as CVE-2026-4689 since 03/24/2026. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. 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 07/01/2026).

The vulnerability scanner Nessus provides a plugin with the ID 303470 (Mozilla Firefox ESR < 115.34), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 149 eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (303470) and CERT Bund (WID-SEC-2026-0850). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Affected

  • Debian Linux
  • Amazon Linux 2
  • Red Hat Enterprise Linux
  • SUSE Linux
  • Oracle Linux
  • SUSE openSUSE
  • RESF Rocky Linux
  • Mozilla Firefox
  • Mozilla Firefox ESR
  • 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: 8.8
VulDB Meta Temp Score: 8.7

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 10.0
NVD Vector: 🔒

ADP CISA Base Score: 10.0
ADP CISA Vector: 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Integer overflow
CWE: CWE-190 / CWE-189
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: 303470
Nessus Name: Mozilla Firefox ESR < 115.34

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Firefox 149

Timelineinfo

03/24/2026 Advisory disclosed
03/24/2026 +0 days CVE reserved
03/24/2026 +0 days VulDB entry created
07/01/2026 +99 days VulDB entry last update

Sourcesinfo

Vendor: mozilla.org
Product: mozilla.org

Advisory: bugzilla.mozilla.org
Status: Confirmed

CVE: CVE-2026-4689 (🔒)
GCVE (CVE): GCVE-0-2026-4689
GCVE (VulDB): GCVE-100-352736
CERT Bund: WID-SEC-2026-0850 - Mozilla Firefox und Mozilla Thunderbird: Mehrere Schwachstellen

Entryinfo

Created: 03/24/2026 14:17
Updated: 07/01/2026 21:30
Changes: 03/24/2026 14:17 (55), 03/25/2026 01:45 (2), 03/28/2026 17:15 (22), 04/14/2026 09:46 (7), 04/15/2026 13:26 (1), 07/01/2026 21:30 (1)
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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