Mozilla thin-vec up to 0.2.15 clear use after free

CVSS Meta Temp Score
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CTI Interest Score
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4.5$0-$5k0.00

Summaryinfo

A vulnerability marked as critical has been reported in Mozilla thin-vec up to 0.2.15. The impacted element is the function IntoIter::drop/ThinVec::clear. Performing a manipulation results in use after free. This vulnerability is cataloged as CVE-2026-6654. There is no exploit available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability classified as problematic has been found in Mozilla thin-vec up to 0.2.15. This affects the function IntoIter::drop/ThinVec::clear. The manipulation with an unknown input leads to a use after free vulnerability. CWE is classifying the issue as CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. This is going to have an impact on availability. The summary by CVE is:

Double-Free / Use-After-Free (UAF) in the `IntoIter::drop` and `ThinVec::clear` functions in the thin_vec crate. A panic in `ptr::drop_in_place` skips setting the length to zero.

The weakness was shared by Juhyung Son as GHSA-xphw-cqx3-667j. It is possible to read the advisory at github.com. This vulnerability is uniquely identified as CVE-2026-6654 since 04/20/2026. The exploitability is told to be easy. Technical details of the vulnerability are known, but there is no available exploit. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 07/02/2026).

The vulnerability scanner Nessus provides a plugin with the ID 314585 (Amazon Linux 2 : firefox, --advisory ALAS2FIREFOX-2026-058 (ALASFIREFOX-2026-058)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 0.2.16 eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (314585) and EUVD (EUVD-2026-23832). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.6
VulDB Meta Temp Score: 4.5

VulDB Base Score: 3.5
VulDB Temp Score: 3.4
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 5.1
NVD Vector: 🔒

ADP CISA Base Score: 5.1
ADP CISA Vector: 🔒

CVSSv2info

AVACAuCIA
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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: Partially
Local: Yes
Remote: Partially

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 314585
Nessus Name: Amazon Linux 2 : firefox, --advisory ALAS2FIREFOX-2026-058 (ALASFIREFOX-2026-058)

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: thin-vec 0.2.16

Timelineinfo

04/20/2026 Advisory disclosed
04/20/2026 +0 days CVE reserved
04/20/2026 +0 days VulDB entry created
07/02/2026 +73 days VulDB entry last update

Sourcesinfo

Vendor: mozilla.org
Product: github.com

Advisory: GHSA-xphw-cqx3-667j
Researcher: Juhyung Son
Status: Confirmed

CVE: CVE-2026-6654 (🔒)
GCVE (CVE): GCVE-0-2026-6654
GCVE (VulDB): GCVE-100-358299
EUVD: 🔒

Entryinfo

Created: 04/20/2026 13:37
Updated: 07/02/2026 07:21
Changes: 04/20/2026 13:37 (58), 04/20/2026 16:24 (1), 05/14/2026 19:00 (2), 07/02/2026 07:21 (20)
Complete: 🔍
Cache ID: 216::103

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

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