libexpat up to 2.8.1 use after free

CVSS Meta Temp Score
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CTI Interest Score
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5.0$0-$5k0.00

Summaryinfo

A vulnerability categorized as critical has been discovered in libexpat up to 2.8.1. The affected element is the function XML_GetBuffer/XML_Parse/XML_ParseBuffer/XML_ParserFree/XML_ParserReset. Such manipulation leads to use after free. This vulnerability is traded as CVE-2026-50219. An attack has to be approached locally. There is no exploit available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as critical, has been found in libexpat up to 2.8.1. Affected by this issue is the function XML_GetBuffer/XML_Parse/XML_ParseBuffer/XML_ParserFree/XML_ParserReset. The manipulation with an unknown input leads to a use after free vulnerability. Using CWE to declare the problem leads to CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. Impacted is confidentiality, integrity, and availability. CVE summarizes:

libexpat before 2.8.2 lacks handler call depth tracking for calls to XML_GetBuffer, XML_Parse, XML_ParseBuffer, XML_ParserFree, or XML_ParserReset from within handlers in cases of a policy violation. Thus, a use-after-free can occur,

The advisory is shared for download at github.com. This vulnerability is handled as CVE-2026-50219 since 06/04/2026. The exploitation is known to be easy. The attack needs to be approached locally. There are known technical details, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 318662 (Linux Distros Unpatched Vulnerability : CVE-2026-50219), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 2.8.2 eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (318662) and EUVD (EUVD-2026-34206). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.1
VulDB Meta Temp Score: 5.0

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

CNA Base Score: 4.9
CNA Vector (MITRE): 🔒

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: Partially
Local: Yes
Remote: No

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 318662
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2026-50219

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: libexpat 2.8.2

Timelineinfo

06/04/2026 Advisory disclosed
06/04/2026 +0 days CVE reserved
06/04/2026 +0 days VulDB entry created
06/05/2026 +1 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-50219 (🔒)
GCVE (CVE): GCVE-0-2026-50219
GCVE (VulDB): GCVE-100-368264
EUVD: 🔒

Entryinfo

Created: 06/04/2026 07:52
Updated: 06/05/2026 03:44
Changes: 06/04/2026 07:52 (63), 06/04/2026 09:57 (1), 06/05/2026 03:44 (2)
Complete: 🔍
Cache ID: 216::103

VulDB is the best source for vulnerability data and more expert information about this specific topic.

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