libexpat up to 2.7.3 XML_ExternalEntityParserCreate null pointer dereference

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

Summaryinfo

A vulnerability was found in libexpat up to 2.7.3. It has been classified as problematic. Affected by this vulnerability is the function XML_ExternalEntityParserCreate. This manipulation causes null pointer dereference. The identification of this vulnerability is CVE-2026-24515. The attack can only be executed locally. There is no exploit available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability was found in libexpat up to 2.7.3. It has been declared as problematic. Affected by this vulnerability is the function XML_ExternalEntityParserCreate. The manipulation with an unknown input leads to a null pointer dereference vulnerability. The CWE definition for the vulnerability is CWE-476. A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit. As an impact it is known to affect availability. The summary by CVE is:

In libexpat before 2.7.4, XML_ExternalEntityParserCreate does not copy unknown encoding handler user data.

The advisory is shared at github.com. This vulnerability is known as CVE-2026-24515 since 01/23/2026. The exploitation appears to be difficult. An attack has to be approached locally. Technical details are known, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 296261 (Linux Distros Unpatched Vulnerability : CVE-2026-24515), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 2.7.4 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (296261). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 2.6
VulDB Meta Temp Score: 2.6

VulDB Base Score: 2.5
VulDB Temp Score: 2.4
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 2.5
NVD Vector: 🔒

CNA Base Score: 2.9
CNA Vector (MITRE): 🔒

CVSSv2info

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

Exploitinginfo

Class: Null pointer dereference
CWE: CWE-476 / CWE-404
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: 296261
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2026-24515

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: libexpat 2.7.4

Timelineinfo

01/23/2026 Advisory disclosed
01/23/2026 +0 days CVE reserved
01/23/2026 +0 days VulDB entry created
06/02/2026 +130 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-24515 (🔒)
GCVE (CVE): GCVE-0-2026-24515
GCVE (VulDB): GCVE-100-342529

Entryinfo

Created: 01/23/2026 09:05
Updated: 06/02/2026 19:21
Changes: 01/23/2026 09:05 (63), 01/23/2026 23:42 (2), 01/31/2026 06:11 (11), 02/06/2026 00:03 (8), 06/02/2026 19:21 (1)
Complete: 🔍
Cache ID: 216::103

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

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