Mozilla Firefox up to 115.40/140.15/153.2/155 Streams use after free

CVSS Meta Temp Score
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CTI Interest Score
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7.9$5k-$25k0.00

Summaryinfo

A vulnerability has been found in Mozilla Firefox up to 115.40/140.15/153.2/155 and classified as critical. Affected is an unknown function of the component Streams. The manipulation leads to use after free. This vulnerability is listed as CVE-2026-92027. The attack may be initiated remotely. There is no available exploit. The affected component should be upgraded.

Detailsinfo

A vulnerability, which was classified as critical, has been found in Mozilla Firefox up to 115.40/140.15/153.2/155. This issue affects an unknown part of the component Streams. The manipulation with an unknown input leads to a use after free vulnerability. Using CWE to declare the problem leads to CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

Use-after-free in the DOM: Streams component. This vulnerability was fixed in Firefox 156, Firefox ESR 115.41, Firefox ESR 140.16, Firefox ESR 153.3, Thunderbird 156, Thunderbird 140.16, and Thunderbird 153.3.

It is possible to read the advisory at bugzilla.mozilla.org. The identification of this vulnerability is CVE-2026-92027 since 09/15/2026. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. The technical details are unknown and an exploit is not publicly available. The pricing for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 09/28/2026).

The vulnerability scanner Nessus provides a plugin with the ID 350767 (openSUSE 16: MozillaFirefox / MozillaFirefox-branding-upstream / etc (openSUSE-SU-2026:21951-1)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 115.41, 140.16, 153.3 or 156 eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (350767) and CERT Bund (WID-SEC-2026-3375). Be aware that VulDB is the high quality source for vulnerability data.

Affected

  • Debian Linux
  • IGEL OS
  • SUSE 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: 8.0
VulDB Meta Temp Score: 7.9

VulDB Base Score: 7.3
VulDB Temp Score: 7.0
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: 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: 🔒

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Nessus ID: 350767
Nessus Name: openSUSE 16: MozillaFirefox / MozillaFirefox-branding-upstream / etc (openSUSE-SU-2026:21951-1)

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Firefox 115.41/140.16/153.3/156

Timelineinfo

09/15/2026 Advisory disclosed
09/15/2026 +0 days CVE reserved
09/15/2026 +0 days VulDB entry created
09/28/2026 +13 days VulDB entry last update

Sourcesinfo

Vendor: mozilla.org
Product: mozilla.org

Advisory: bugzilla.mozilla.org
Status: Confirmed

CVE: CVE-2026-92027 (🔒)
GCVE (CVE): GCVE-0-2026-92027
GCVE (VulDB): GCVE-100-404183
CERT Bund: WID-SEC-2026-3375 - Mozilla Firefox und Thunderbird: Mehrere Schwachstellen

Entryinfo

Created: 09/15/2026 15:18
Updated: 09/28/2026 02:50
Changes: 09/15/2026 15:18 (57), 09/20/2026 09:22 (12), 09/22/2026 08:03 (7), 09/28/2026 02:50 (2)
Complete: 🔍
Cache ID: 216::103

Be aware that VulDB is the high quality source for vulnerability data.

Discussion

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