Vulnerability Report

CVE-2026-56407

Title: Integer Overflow in libexpat doProlog

Memory Corruption

Proof Of Concept

No public PoC currently indexed for CVE-2026-56407.

CWE Category CWE-190

Published Date Jun 21, 2026

Modified Date Jun 23, 2026

Exploit Status Not Found

Score 6.9 CVSS v3.1

Exploit Probability (EPSS)

0.10%

Vulnerability Summary

CVE-2026-56407: libexpat before 2.8.2 has an integer overflow in doProlog that is related to storeEntityValue and entity textLen.

Impacted Vendors

libexpat_project 1

Reference Links

https://github.com/libexpat/libexpat/pull/1262

CVSS v3.1

Source Entity [email protected]

Severity MEDIUM

6.9

Attack Vector

LOCAL

Complexity

HIGH

Privileges

N/A

Interaction

NONE

Confidentiality

N/A

Integrity

N/A

Availability

N/A

Scope

UNCHANGED

RAW VECTOR CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:L

Associated Attack Patterns (CAPEC)

Total: Patterns

CVE-2026-56407 Exploits & PoCs (Proof Of Concept)

No public PoCs found in our database for this CVE.

June 23, 2026 MODIFIED

Vulnerability data updated via NVD.

June 22, 2026 MODIFIED

Vulnerability data updated via NVD.

June 21, 2026 MODIFIED

Vulnerability data updated via NVD.

Attack Vector Matrix

Access Vector LOCAL

Complexity HIGH

Privileges N/A

Interaction NONE

CVSS Vector String


                                    CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:L

Affected Stack

No specific products linked.