Mozilla Thunderbird Garbage Collection use after free

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.2$5k-$25k0.00

Summaryinfo

A vulnerability, which was classified as critical, was found in Mozilla Thunderbird. The affected element is an unknown function of the component Garbage Collection. Executing a manipulation can lead to use after free. This vulnerability is handled as CVE-2023-5171. The attack can be executed remotely. There is not any exploit available. You should upgrade the affected component.

Detailsinfo

A vulnerability has been found in Mozilla Thunderbird (Mail Client Software) (affected version not known) and classified as critical. This vulnerability affects some unknown functionality of the component Garbage Collection. The manipulation with an unknown input leads to a use after free vulnerability. The CWE definition for the vulnerability is CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

During Ion compilation, a Garbage Collection could have resulted in a use-after-free condition, allowing an attacker to write two NUL bytes, and cause a potentially exploitable crash. This vulnerability affects Firefox < 118, Firefox ESR < 115.3, and Thunderbird < 115.3.

The weakness was released 09/27/2023. The advisory is available at mozilla.org. This vulnerability was named CVE-2023-5171 since 09/25/2023. 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 06/21/2025).

The vulnerability scanner Nessus provides a plugin with the ID 239741 (TencentOS Server 3: firefox (TSSA-2023:0238)), which helps to determine the existence of the flaw in a target environment.

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

The vulnerability is also documented in the vulnerability database at Tenable (239741). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

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Vendor

Name

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: Use after free
CWE: CWE-416 / 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: 239741
Nessus Name: TencentOS Server 3: firefox (TSSA-2023:0238)

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: mozilla.org

Timelineinfo

09/25/2023 🔍
09/27/2023 +2 days 🔍
09/27/2023 +0 days 🔍
06/21/2025 +633 days 🔍

Sourcesinfo

Vendor: mozilla.org

Advisory: DLA 3587-1
Status: Confirmed

CVE: CVE-2023-5171 (🔍)
GCVE (CVE): GCVE-0-2023-5171
GCVE (VulDB): GCVE-100-240466

Entryinfo

Created: 09/27/2023 18:20
Updated: 06/21/2025 11:26
Changes: 09/27/2023 18:20 (39), 10/19/2023 09:58 (1), 10/19/2023 10:00 (11), 06/21/2025 11:26 (17)
Complete: 🔍
Cache ID: 216::103

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

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