QuickJS/QuickJS-ng JS_ReadString heap-based overflow

CVSS Meta Temp Score
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CTI Interest Score
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5.9$0-$5k0.00

Summaryinfo

A vulnerability identified as critical has been detected in QuickJS and QuickJS-ng. This affects the function JS_ReadString. This manipulation causes heap-based overflow. This vulnerability is registered as CVE-2025-46687. The attack needs to be launched locally. No exploit is available. You should upgrade the affected component.

Detailsinfo

A vulnerability was found in QuickJS and QuickJS-ng (affected version not known). It has been declared as critical. Affected by this vulnerability is the function JS_ReadString. The manipulation with an unknown input leads to a heap-based overflow vulnerability. The CWE definition for the vulnerability is CWE-122. A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc(). As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

quickjs-ng through 0.9.0 has a missing length check in JS_ReadString for a string, leading to a heap-based buffer overflow. QuickJS before 2025-04-26 is also affected.

The advisory is shared at github.com. This vulnerability is known as CVE-2025-46687 since 04/27/2025. The exploitation appears to be difficult. An attack has to be approached locally. Technical details are known, but no exploit is available.

Upgrading eliminates this vulnerability. Applying the patch 1eb05e44fad89daafa8ee3eb74b8520b4a37ec9a is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2025-12428). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

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License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.0
VulDB Meta Temp Score: 5.9

VulDB Base Score: 4.5
VulDB Temp Score: 4.3
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 7.8
NVD Vector: 🔍

CNA Base Score: 5.6
CNA Vector (MITRE): 🔍

CVSSv2info

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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Heap-based overflow
CWE: CWE-122 / CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: No

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Patch: 1eb05e44fad89daafa8ee3eb74b8520b4a37ec9a

Timelineinfo

04/27/2025 🔍
04/28/2025 +1 days 🔍
04/28/2025 +0 days 🔍
01/14/2026 +261 days 🔍

Sourcesinfo

Advisory: 399
Status: Confirmed

CVE: CVE-2025-46687 (🔍)
GCVE (CVE): GCVE-0-2025-46687
GCVE (VulDB): GCVE-100-306385
EUVD: 🔍

Entryinfo

Created: 04/28/2025 07:47
Updated: 01/14/2026 19:27
Changes: 04/28/2025 07:47 (64), 05/25/2025 21:15 (1), 01/14/2026 19:27 (12)
Complete: 🔍
Cache ID: 216::103

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

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