servo smallbitvec up to 2.6.0 on Rust heap-based overflow

CVSS Meta Temp Score
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CTI Interest Score
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6.2$0-$5k0.00

Summaryinfo

A vulnerability classified as critical has been found in servo smallbitvec up to 2.6.0 on Rust. This issue affects some unknown processing. This manipulation causes heap-based overflow. This vulnerability is registered as CVE-2026-44983. The attack needs to be launched locally. No exploit is available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability was found in servo smallbitvec up to 2.6.0 on Rust. It has been declared as critical. Affected by this vulnerability is some unknown processing. 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:

smallbitvec is a growable bit-vector for Rust, optimized for size. From 1.0.1 to 2.6.0, an integer overflow in the internal capacity calculation of smallbitvec can lead to an undersized heap allocation, resulting in a heap buffer overflow through safe APIs only. This allows memory corruption without requiring unsafe code from the caller. This vulnerability is fixed in 2.6.1.

It is possible to read the advisory at github.com. This vulnerability is known as CVE-2026-44983 since 05/08/2026. The exploitation appears to be easy. Attacking locally is a requirement. The technical details are unknown and an exploit is not publicly available.

Upgrading to version 2.6.1 eliminates this vulnerability.

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

Productinfo

Type

Vendor

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.3
VulDB Meta Temp Score: 6.2

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 7.3
CNA Vector (GitHub_M): 🔒

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: 🔒

Upgrade: smallbitvec 2.6.1

Timelineinfo

05/08/2026 CVE reserved
05/27/2026 +19 days Advisory disclosed
05/27/2026 +0 days VulDB entry created
05/27/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: GHSA-97wc-2hqc-cjgr
Status: Confirmed

CVE: CVE-2026-44983 (🔒)
GCVE (CVE): GCVE-0-2026-44983
GCVE (VulDB): GCVE-100-365875

Entryinfo

Created: 05/27/2026 06:53
Changes: 05/27/2026 06:53 (66)
Complete: 🔍
Cache ID: 216::103

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

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