Mozilla Thunderbird up to 141 memory corruption

CVSS Meta Temp Score
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CTI Interest Score
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6.0$5k-$25k0.00

Summaryinfo

A vulnerability classified as critical has been found in Mozilla Thunderbird up to 141. This vulnerability affects unknown code. Performing a manipulation results in memory corruption. This vulnerability is reported as CVE-2025-9187. The attack is possible to be carried out remotely. No exploit exists. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability classified as critical has been found in Mozilla Thunderbird up to 141. This affects 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. The summary by CVE is:

Memory safety bugs present in Firefox 141 and Thunderbird 141. 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 affects Firefox < 142 and Thunderbird < 142.

The advisory is shared at bugzilla.mozilla.org. This vulnerability is uniquely identified as CVE-2025-9187 since 08/19/2025. The exploitability is told to be easy. It is possible to initiate the attack remotely. No form of authentication is needed for 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 10/12/2025).

The vulnerability scanner Nessus provides a plugin with the ID 258109 (SUSE SLED15 / SLES15 / openSUSE 15 Security Update : MozillaFirefox (SUSE-SU-2025:03008-1)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 142 eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (258109) and CERT Bund (WID-SEC-2025-1866). 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: 6.3
VulDB Meta Temp Score: 6.0

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

CVSSv2info

AVACAuCIA
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💳💳💳💳💳💳
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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: 🔒

0-DayUnlockUnlockUnlockUnlock
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Nessus ID: 258109
Nessus Name: SUSE SLED15 / SLES15 / openSUSE 15 Security Update : MozillaFirefox (SUSE-SU-2025:03008-1)

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Thunderbird 142

Timelineinfo

08/19/2025 CVE reserved
08/19/2025 +0 days VulDB entry created
08/20/2025 +0 days Advisory disclosed
10/12/2025 +53 days VulDB entry last update

Sourcesinfo

Vendor: mozilla.org

Advisory: bugzilla.mozilla.org
Status: Confirmed

CVE: CVE-2025-9187 (🔒)
GCVE (CVE): GCVE-0-2025-9187
GCVE (VulDB): GCVE-100-320697
CERT Bund: WID-SEC-2025-1866 - Mozilla Firefox und Thunderbird: Mehrere Schwachstellen

Entryinfo

Created: 08/20/2025 00:20
Updated: 10/12/2025 16:28
Changes: 08/20/2025 00:20 (55), 08/30/2025 02:03 (2), 09/07/2025 07:16 (7), 10/12/2025 16:28 (1)
Complete: 🔍
Cache ID: 216::103

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

Discussion

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