VulnerabilityModified
CVE-2026-45186
In libexpat before 2.8.1, the computational complexity of attribute name collision checks allows a denial of service via moderately sized crafted XML input.
HIGH 7.5EPSS 0.46%
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.46%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
In libexpat before 2.8.1, the computational complexity of attribute name collision checks allows a denial of service via moderately sized crafted XML input.
- CVSS 3.1
- 7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- EPSS
- 0.46% probability · 39th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-407
- Affected
- libexpat project/libexpat
- Source
- cve@mitre.org
References
- https://github.com/libexpat/libexpat/pull/1216Exploit, Issue Tracking, Patch
- http://www.openwall.com/lists/oss-security/2026/05/11/16Mailing List, Third Party Advisory
- https://access.redhat.com/errata/RHSA-2026:22715
- https://access.redhat.com/errata/RHSA-2026:22721
- https://access.redhat.com/errata/RHSA-2026:23230
- https://access.redhat.com/errata/RHSA-2026:26319
- https://access.redhat.com/errata/RHSA-2026:27201
- https://access.redhat.com/errata/RHSA-2026:29197
- https://access.redhat.com/errata/RHSA-2026:58981
- https://access.redhat.com/security/cve/CVE-2026-45186
- https://bugzilla.redhat.com/show_bug.cgi?id=2468575
- https://cert-portal.siemens.com/productcert/html/ssa-082556.html
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-45186.json
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.