libexpat up to 2.7.4 infinite loop

CVSS Meta Temp Score
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CTI Interest Score
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4.2$0-$5k0.00

Summaryinfo

A vulnerability has been found in libexpat up to 2.7.4 and classified as problematic. This affects an unknown part. The manipulation leads to infinite loop. This vulnerability is documented as CVE-2026-32777. The attack needs to be performed locally. There is not any exploit available. The affected component should be upgraded.

Detailsinfo

A vulnerability was found in libexpat up to 2.7.4 and classified as problematic. This issue affects an unknown part. The manipulation with an unknown input leads to a infinite loop vulnerability. Using CWE to declare the problem leads to CWE-835. The product contains an iteration or loop with an exit condition that cannot be reached, i.e., an infinite loop. Impacted is availability. The summary by CVE is:

libexpat before 2.7.5 allows an infinite loop while parsing DTD content.

The advisory is shared at github.com. The identification of this vulnerability is CVE-2026-32777 since 03/16/2026. The exploitation is known to be easy. An attack has to be approached locally. Neither technical details nor an exploit are publicly available.

The vulnerability scanner Nessus provides a plugin with the ID 302508 (Linux Distros Unpatched Vulnerability : CVE-2026-32777), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 2.7.5 eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (302508), EUVD (EUVD-2026-12349) and CERT Bund (WID-SEC-2026-0733). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Affected

  • Open Source expat

Productinfo

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.3
VulDB Meta Temp Score: 4.2

VulDB Base Score: 3.3
VulDB Temp Score: 3.2
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 5.5
NVD Vector: 🔒

CNA Base Score: 4.0
CNA Vector (MITRE): 🔒

CVSSv2info

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

Exploitinginfo

Class: Infinite loop
CWE: CWE-835 / 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: 302508
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2026-32777

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: libexpat 2.7.5

Timelineinfo

03/16/2026 Advisory disclosed
03/16/2026 +0 days CVE reserved
03/16/2026 +0 days VulDB entry created
03/21/2026 +5 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-32777 (🔒)
GCVE (CVE): GCVE-0-2026-32777
GCVE (VulDB): GCVE-100-351221
EUVD: 🔒
CERT Bund: WID-SEC-2026-0733 - libexpat: Mehrere Schwachstellen ermöglichen Denial of Service

Entryinfo

Created: 03/16/2026 09:53
Updated: 03/21/2026 01:14
Changes: 03/16/2026 09:53 (62), 03/16/2026 10:14 (1), 03/16/2026 15:16 (7), 03/16/2026 22:13 (2), 03/21/2026 01:14 (12)
Complete: 🔍
Cache ID: 216::103

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

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