Mozilla Firefox 153.1/154 memory corruption

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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7.2$5k-$25k0.00

Summaryinfo

A vulnerability has been found in Mozilla Firefox 153.1/154 and classified as critical. Affected by this vulnerability is an unknown functionality. Performing a manipulation results in memory corruption. This vulnerability is reported as CVE-2026-84144. The attack is possible to be carried out remotely. No exploit exists. The affected component should be upgraded.

Detailsinfo

A vulnerability was found in Mozilla Firefox 153.1/154. It has been classified as critical. This affects an unknown part. 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. The summary by CVE is:

Internally found bugs present in Thunderbird 154 and Thunderbird ESR 153.1. Some of these bugs showed evidence of memory corruption or another security-relevant defect and we presume that with enough effort some of these could have been exploited. This vulnerability was fixed in Firefox 155, Firefox ESR 153.2, Thunderbird 155, and Thunderbird 153.2.

This vulnerability is uniquely identified as CVE-2026-84144 since 09/01/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. 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 09/08/2026).

The vulnerability scanner Nessus provides a plugin with the ID 342304 (Linux Distros Unpatched Vulnerability : CVE-2026-84144), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 153.2 or 155 eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (342304) and CERT Bund (WID-SEC-2026-3132). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Affected

  • Debian Linux
  • SUSE openSUSE
  • 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: 7.4
VulDB Meta Temp Score: 7.2

VulDB Base Score: 7.3
VulDB Temp Score: 7.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

ADP CISA Base Score: 7.5
ADP CISA Vector: 🔒

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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Nessus ID: 342304
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2026-84144

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Firefox 153.2/155

Timelineinfo

09/01/2026 Advisory disclosed
09/01/2026 +0 days CVE reserved
09/01/2026 +0 days VulDB entry created
09/08/2026 +7 days VulDB entry last update

Sourcesinfo

Vendor: mozilla.org
Product: mozilla.org

Status: Confirmed

CVE: CVE-2026-84144 (🔒)
GCVE (CVE): GCVE-0-2026-84144
GCVE (VulDB): GCVE-100-397617
CERT Bund: WID-SEC-2026-3132 - Mozilla Firefox und Thunderbird: Mehrere Schwachstellen

Entryinfo

Created: 09/01/2026 15:10
Updated: 09/08/2026 10:41
Changes: 09/01/2026 15:10 (53), 09/03/2026 02:18 (2), 09/07/2026 06:44 (12), 09/08/2026 10:41 (7)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Discussion

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