Mozilla Thunderbird up to 140.15 memory corruption

CVSS Meta Temp Score
CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.
Current Exploit Price (≈)
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CTI Interest Score
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7.0$5k-$25k0.42+

Summaryinfo

A vulnerability was found in Mozilla Thunderbird up to 140.15. It has been declared as critical. This affects an unknown function. The manipulation results in memory corruption. This vulnerability is identified as CVE-2026-92238. The attack can be executed remotely. There is not any exploit available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability classified as critical has been found in Mozilla Thunderbird up to 140.15. Affected is some unknown processing. 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. CVE summarizes:

A maliciously constructed mail header could lead to multiple fields being parsed as one, or potential memory safety violations. This vulnerability was fixed in Thunderbird 156 and Thunderbird 140.16.

The advisory is shared for download at bugzilla.mozilla.org. This vulnerability is traded as CVE-2026-92238 since 09/15/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. 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 09/15/2026).

Upgrading to version 140.16 eliminates this vulnerability.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.3
VulDB Meta Temp Score: 7.0

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

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
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Thunderbird 140.16

Timelineinfo

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

Sourcesinfo

Vendor: mozilla.org

Advisory: bugzilla.mozilla.org
Status: Confirmed

CVE: CVE-2026-92238 (🔒)
GCVE (CVE): GCVE-0-2026-92238
GCVE (VulDB): GCVE-100-404676

Entryinfo

Created: 09/15/2026 22:11
Changes: 09/15/2026 22:11 (56)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

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