Mozilla Firefox up to 150 memory corruption

CVSS Meta Temp Score
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CTI Interest Score
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7.4$5k-$25k0.00

Summaryinfo

A vulnerability was found in Mozilla Firefox up to 150. It has been classified as critical. Affected is an unknown function. The manipulation leads to memory corruption. This vulnerability is traded as CVE-2026-8974. It is possible to initiate the attack remotely. There is no exploit available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability was found in Mozilla Firefox up to 150 and classified as critical. This issue affects an unknown code block. The manipulation with an unknown input leads to a memory corruption vulnerability. Using CWE to declare the problem leads to 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. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

Memory safety bugs present in Thunderbird 140.10 and Thunderbird 150. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.

The identification of this vulnerability is CVE-2026-8974 since 05/19/2026. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. 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 06/17/2026).

The vulnerability scanner Nessus provides a plugin with the ID 315327 (Mozilla Firefox < 151.0), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 151 eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (315327), EUVD (EUVD-2026-30922) and CERT Bund (WID-SEC-2026-1606). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Affected

  • Debian Linux
  • Amazon Linux 2
  • 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: 7.6
VulDB Meta Temp Score: 7.4

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

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: 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: 315327
Nessus Name: Mozilla Firefox < 151.0

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Firefox 151

Timelineinfo

05/19/2026 Advisory disclosed
05/19/2026 +0 days CVE reserved
05/19/2026 +0 days VulDB entry created
06/17/2026 +29 days VulDB entry last update

Sourcesinfo

Vendor: mozilla.org
Product: mozilla.org

Status: Confirmed

CVE: CVE-2026-8974 (🔒)
GCVE (CVE): GCVE-0-2026-8974
GCVE (VulDB): GCVE-100-364649
EUVD: 🔒
CERT Bund: WID-SEC-2026-1606 - Mozilla Firefox und Thunderbird: Mehrere Schwachstellen

Entryinfo

Created: 05/19/2026 15:50
Updated: 06/17/2026 22:17
Changes: 05/19/2026 15:50 (54), 05/20/2026 01:57 (2), 05/20/2026 11:04 (1), 05/23/2026 13:55 (12), 06/17/2026 22:17 (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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