Mozilla Thunderbird up to 102.9 Javascript Code 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 (≈) Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.	CTI Interest Score Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
6.0	$5k-$25k	0.00

Summaryinfo

A vulnerability categorized as critical has been discovered in Mozilla Thunderbird up to 102.9. This issue affects some unknown processing of the component Javascript Code Handler. Such manipulation leads to memory corruption. This vulnerability is referenced as CVE-2023-29536. It is possible to launch the attack remotely. No exploit is available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as critical, has been found in Mozilla Thunderbird up to 102.9 (Mail Client Software). Affected by this issue is an unknown functionality of the component Javascript Code Handler. The manipulation with an unknown input leads to a memory corruption vulnerability. Using CWE to declare the problem leads to 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. Impacted is confidentiality, integrity, and availability.

The weakness was published 04/11/2023 by zx as Bug 1821959 as confirmed advisory (Website). The advisory is available at bugzilla.mozilla.org. The advisory contains:

An attacker could cause the memory manager to incorrectly free a pointer that addresses attacker-controlled memory, resulting in an assertion, memory corruption, or a potentially exploitable crash.

This vulnerability is handled as CVE-2023-29536. Successful exploitation requires user interaction by the victim. The technical details are unknown and an exploit is not available. The structure of the vulnerability defines a possible price range of USD $5k-$25k at the moment (estimation calculated on 12/10/2025).

The vulnerability scanner Nessus provides a plugin with the ID 239763 (TencentOS Server 4: thunderbird (TSSA-2024:0450)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 102.10 eliminates this vulnerability. A possible mitigation has been published immediately after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at Tenable (239763) and EUVD (EUVD-2023-33078). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Type

• Mail Client Software

Vendor

• Mozilla

Name

• Thunderbird

Version

• 102.0
• 102.1
• 102.2
• 102.3
• 102.4
• 102.5
• 102.6
• 102.7
• 102.8
• 102.9

License

• open-source

Website

• Vendor: https://www.mozilla.org/

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

AV	AC	Au	C	I	A
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳

Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock

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-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Nessus ID: 239763
Nessus Name: TencentOS Server 4: thunderbird (TSSA-2024:0450)

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

Reaction Time: 🔍
0-Day Time: 🔍
Exposure Time: 🔍

Upgrade: Thunderbird 102.10

Timelineinfo

04/07/2023 🔍
04/11/2023 +4 days 🔍
04/11/2023 +0 days 🔍
04/14/2023 +3 days 🔍
12/10/2025 +971 days 🔍

Sourcesinfo

Vendor: mozilla.org

Advisory: Bug 1821959
Researcher: zx
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2023-29536 (🔍)
GCVE (CVE): GCVE-0-2023-29536
GCVE (VulDB): GCVE-100-226010
EUVD: 🔍

Entryinfo

Created: 04/14/2023 16:43
Updated: 12/10/2025 12:30
Changes: 04/14/2023 16:43 (2), 04/14/2023 16:44 (16), 04/14/2023 16:47 (28), 05/03/2023 13:48 (1), 06/20/2025 19:31 (17), 12/10/2025 12:30 (1)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Discussion

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