Mozilla Thunderbird up to 140 on 64-bit IonMonkey-JIT return value

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

Summaryinfo

A vulnerability has been found in Mozilla Thunderbird up to 140 on 64-bit and classified as critical. Impacted is an unknown function of the component IonMonkey-JIT. Performing a manipulation results in return value. This vulnerability is known as CVE-2025-8027. Remote exploitation of the attack is possible. No exploit is available. The affected component should be upgraded.

Detailsinfo

A vulnerability was found in Mozilla Thunderbird up to 140 on 64-bit. It has been classified as critical. This affects an unknown part of the component IonMonkey-JIT. The manipulation with an unknown input leads to a return value vulnerability. CWE is classifying the issue as CWE-252. The product does not check the return value from a method or function, which can prevent it from detecting unexpected states and conditions. The impact remains unknown. The summary by CVE is:

On 64-bit platforms IonMonkey-JIT only wrote 32 bits of the 64-bit return value space on the stack. Baseline-JIT, however, read the entire 64 bits. This vulnerability affects Firefox < 141, Firefox ESR < 115.26, Firefox ESR < 128.13, Firefox ESR < 140.1, Thunderbird < 141, Thunderbird < 128.13, and Thunderbird < 140.1.

It is possible to read the advisory at bugzilla.mozilla.org. This vulnerability is uniquely identified as CVE-2025-8027 since 07/22/2025. 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. 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 08/08/2025).

The vulnerability scanner Nessus provides a plugin with the ID 242581 (Mozilla Thunderbird < 128.13), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 141 eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (242581) and CERT Bund (WID-SEC-2025-1623). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Affected

  • Debian Linux
  • Amazon Linux 2
  • Red Hat Enterprise Linux
  • Fedora Linux
  • SUSE Linux
  • Oracle Linux
  • SUSE openSUSE
  • IGEL OS
  • 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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💳💳💳💳💳💳
💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Return value
CWE: CWE-252 / CWE-253
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: 242581
Nessus Name: Mozilla Thunderbird < 128.13

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Thunderbird 141

Timelineinfo

07/22/2025 CVE reserved
07/23/2025 +1 days Advisory disclosed
07/23/2025 +0 days VulDB entry created
08/08/2025 +16 days VulDB entry last update

Sourcesinfo

Vendor: mozilla.org

Advisory: bugzilla.mozilla.org
Status: Confirmed

CVE: CVE-2025-8027 (🔒)
GCVE (CVE): GCVE-0-2025-8027
GCVE (VulDB): GCVE-100-317355
CERT Bund: WID-SEC-2025-1623 - Mozilla Firefox , Firefox ESR und Thunderbird: Mehrere Schwachstellen

Entryinfo

Created: 07/23/2025 08:32
Updated: 08/08/2025 18:44
Changes: 07/23/2025 08:32 (56), 07/23/2025 14:58 (2), 07/23/2025 17:06 (1), 07/27/2025 08:04 (7), 07/31/2025 21:47 (1), 08/08/2025 18:44 (1)
Complete: 🔍
Cache ID: 216:1C5:103

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Discussion

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