Mozilla Firefox up to 147 Location use after free

CVSS Meta Temp Score
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CTI Interest Score
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8.2$5k-$25k0.00

Summaryinfo

A vulnerability has been found in Mozilla Firefox up to 147 and classified as critical. This vulnerability affects unknown code of the component Location. This manipulation causes use after free. This vulnerability is handled as CVE-2026-2787. The attack can be initiated remotely. There is not any exploit available. The affected component should be upgraded.

Detailsinfo

A vulnerability classified as critical was found in Mozilla Firefox up to 147. Affected by this vulnerability is an unknown part of the component Location. The manipulation with an unknown input leads to a use after free vulnerability. The CWE definition for the vulnerability is CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

Use-after-free in the DOM: Window and Location component. This vulnerability affects Firefox < 148, Firefox ESR < 115.33, Firefox ESR < 140.8, Thunderbird < 148, and Thunderbird < 140.8.

The advisory is shared at bugzilla.mozilla.org. This vulnerability is known as CVE-2026-2787 since 02/19/2026. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. It demands that the victim is doing some kind of user interaction. 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 03/04/2026).

The vulnerability scanner Nessus provides a plugin with the ID 299898 (Linux Distros Unpatched Vulnerability : CVE-2026-2787), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 148 eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (299898) and CERT Bund (WID-SEC-2026-0497). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Affected

  • Debian Linux
  • Red Hat Enterprise Linux
  • SUSE Linux
  • Oracle Linux
  • IGEL OS
  • 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: 8.3
VulDB Meta Temp Score: 8.2

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

NVD Base Score: 9.8
NVD Vector: 🔒

ADP CISA Base Score: 8.8
ADP CISA Vector: 🔒

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: 🔒

0-DayUnlockUnlockUnlockUnlock
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Nessus ID: 299898
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2026-2787

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Firefox 148

Timelineinfo

02/19/2026 CVE reserved
02/24/2026 +5 days Advisory disclosed
02/24/2026 +0 days VulDB entry created
03/04/2026 +8 days VulDB entry last update

Sourcesinfo

Vendor: mozilla.org
Product: mozilla.org

Advisory: bugzilla.mozilla.org
Status: Confirmed

CVE: CVE-2026-2787 (🔒)
GCVE (CVE): GCVE-0-2026-2787
GCVE (VulDB): GCVE-100-347581
CERT Bund: WID-SEC-2026-0497 - Mozilla Firefox, Firefox ESR und Thunderbird: Mehrere Schwachstellen

Entryinfo

Created: 02/24/2026 16:13
Updated: 03/04/2026 01:09
Changes: 02/24/2026 16:13 (56), 02/25/2026 16:49 (2), 02/28/2026 12:07 (21), 03/02/2026 21:09 (7), 03/04/2026 01:09 (1)
Complete: 🔍
Cache ID: 216::103

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

Discussion

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