Mozilla Thunderbird up to 115.1 JIT UpdateRegExpStatics memory corruption

CVSS Meta Temp Score
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CTI Interest Score
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6.2$5k-$25k0.00

Summaryinfo

A vulnerability was found in Mozilla Thunderbird up to 115.1. It has been classified as critical. The affected element is the function UpdateRegExpStatics of the component JIT. This manipulation causes memory corruption. This vulnerability is tracked as CVE-2023-4577. The attack is possible to be carried out remotely. No exploit exists. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability has been found in Mozilla Thunderbird up to 115.1 (Mail Client Software) and classified as critical. Affected by this vulnerability is the function UpdateRegExpStatics of the component JIT. The manipulation with an unknown input leads to a memory corruption vulnerability. The CWE definition for the vulnerability is 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. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

When `UpdateRegExpStatics` attempted to access `initialStringHeap` it could already have been garbage collected prior to entering the function, which could potentially have led to an exploitable crash. This vulnerability affects Firefox < 117, Firefox ESR < 115.2, and Thunderbird < 115.2.

The weakness was disclosed 09/11/2023. The advisory is shared at mozilla.org. This vulnerability is known as CVE-2023-4577 since 08/29/2023. It demands that the victim is doing some kind of user interaction. Technical details are known, but no exploit is available. The price for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 06/20/2025).

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 115.2 eliminates this vulnerability. The upgrade is hosted for download at mozilla.org.

The vulnerability is also documented in the vulnerability database at Tenable (239763). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

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Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.4
VulDB Meta Temp Score: 6.2

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

NVD Base Score: 6.5
NVD Vector: 🔍

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

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: Thunderbird 115.2

Timelineinfo

08/29/2023 🔍
09/11/2023 +13 days 🔍
09/11/2023 +0 days 🔍
06/20/2025 +648 days 🔍

Sourcesinfo

Vendor: mozilla.org

Advisory: mozilla.org
Status: Confirmed

CVE: CVE-2023-4577 (🔍)
GCVE (CVE): GCVE-0-2023-4577
GCVE (VulDB): GCVE-100-239377

Entryinfo

Created: 09/11/2023 15:07
Updated: 06/20/2025 19:42
Changes: 09/11/2023 15:07 (43), 10/04/2023 19:31 (11), 06/20/2025 19:42 (17)
Complete: 🔍
Cache ID: 216::103

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

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