CVE-2026-56403

FAUCET Score

libexpat before 2.8.2 has an integer overflow in storeAtts.

First published: Jun 21, 2026Last modified: Jun 21, 2026

Impacted Technologies

Vendor	Product	Version(s)	CPE
		< 2.8.2CPE matchmatch criteria	cpe:2.3:a:libexpat_project:libexpat::::::::
		>= 0, < 2.8.2CPE match	cpe:2.3:a:libexpat_project:libexpat::::::::

CVSS Data

CVSS version used by this source: 3.1

6.9MEDIUM

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

Attack Vector

LOCAL

Attack Complexity

HIGH

Privileges Required

NONE

User Interaction

NONE

Scope

UNCHANGED

Confidentiality Impact

HIGH

Integrity Impact

HIGH

Availability Impact

LOW

Exploitability Score

1.4

Impact Score

5.5

CvssVersion

3.1

Exploit Intelligence

EPSS Score

0.13%

Probability of exploitation in next 30 days

EPSS Percentile

2.6%

Percentile rank of EPSS score among Peer Group

As of 2026-07-27

Model: v2026.06.15

This CVE's current EPSS score of 0.0013 is in the 2nd percentile among its peer group of 1,595 CVEs.

Social Chatter

The average CVE in this peer group has 0.0 Twitter, 0.0 Reddit, 0.0 Bluesky, 0.0 Mastodon, and 0.1 GitHub mentions.

Media Mentions

No media coverage found for this CVE.

The average CVE in this peer group has 0.0 InfoSec Media, 0.0 Vendor Blog, and 0.0 Security Researcher mentions.

Remediation

Patch Available

Vendor Patches (2)

microsoftpatch availablevia msrc

Product: azl3 expat 2.6.4-6 on Azure Linux 3.0Fixed in: 2.8.2-1

microsoftpatch availablevia msrc

Product: 21279-17084Fixed in: 2.8.2-1

Vendor Advisories (1)

microsoft2026-Jun/CVE-2026-56403Moderate

libexpat before 2.8.2 has an integer overflow in storeAtts.

Jun 9, 2026

References

github.com / libexpat/libexpat/pull/1232

Patch