Mozilla Thunderbird up to 128.7/135 MIME Email Message ui discrepancy

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.5$5k-$25k0.00

Summaryinfo

A vulnerability identified as problematic has been detected in Mozilla Thunderbird up to 128.7/135. This issue affects some unknown processing of the component MIME Email Message Handler. The manipulation leads to ui discrepancy. This vulnerability is referenced as CVE-2025-26696. Remote exploitation of the attack is possible. No exploit is available. You should upgrade the affected component.

Detailsinfo

A vulnerability was found in Mozilla Thunderbird up to 128.7/135. It has been rated as problematic. This issue affects some unknown functionality of the component MIME Email Message Handler. The manipulation with an unknown input leads to a ui discrepancy vulnerability. Using CWE to declare the problem leads to CWE-446. The user interface does not correctly enable or configure a security feature, but the interface provides feedback that causes the user to believe that the feature is in a secure state. Impacted is integrity. The summary by CVE is:

Certain crafted MIME email messages that claimed to contain an encrypted OpenPGP message, which instead contained an OpenPGP signed message, were wrongly shown as being encrypted. This vulnerability was fixed in Thunderbird 136 and Thunderbird 128.8.

The advisory is shared at bugzilla.mozilla.org. The identification of this vulnerability is CVE-2025-26696 since 02/13/2025. 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 04/15/2026).

The vulnerability scanner Nessus provides a plugin with the ID 232679 (SUSE SLED15 / SLES15 / openSUSE 15 Security Update : MozillaThunderbird (SUSE-SU-2025:0849-1)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 128.8 or 136 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (232679). Several companies clearly confirm that VulDB is the primary source for best 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: 5.6
VulDB Meta Temp Score: 5.5

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
VulDB Vector: 🔍
VulDB Reliability: 🔍

ADP CISA Base Score: 7.0
ADP CISA Vector: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Ui discrepancy
CWE: CWE-446
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: 232679
Nessus Name: SUSE SLED15 / SLES15 / openSUSE 15 Security Update : MozillaThunderbird (SUSE-SU-2025:0849-1)

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: Thunderbird 128.8/136

Timelineinfo

02/13/2025 🔍
03/10/2025 +25 days 🔍
03/10/2025 +0 days 🔍
04/15/2026 +401 days 🔍

Sourcesinfo

Vendor: mozilla.org

Advisory: bugzilla.mozilla.org
Status: Confirmed

CVE: CVE-2025-26696 (🔍)
GCVE (CVE): GCVE-0-2025-26696
GCVE (VulDB): GCVE-100-299105

Entryinfo

Created: 03/10/2025 23:34
Updated: 04/15/2026 13:14
Changes: 03/10/2025 23:34 (56), 03/13/2025 17:35 (2), 04/15/2026 13:14 (13)
Complete: 🔍
Cache ID: 216::103

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

Discussion

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