How severe is CVE-2026-45186?

CVE-2026-45186 has a CVSS 3.x base score of 2.9, rated low severity. It is exploitable over local access with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability low.

Is CVE-2026-45186 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (34th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-45186?

CVE-2026-45186 affects Libexpat Project Libexpat. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-45186?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2026-45186 have an EU (EUVD) identifier?

Yes. CVE-2026-45186 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-28985.

When was CVE-2026-45186 published?

CVE-2026-45186 was published on 2026-05-10 and last updated on 2026-06-30.

CVE-2026-45186

CVE-2026-45186 is a low-severity vulnerability in Libexpat Project Libexpat with a CVSS 3.x base score of 2.9. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-407.

Key facts

Severity: Low (CVSS 3.x base score 2.9)
EPSS exploit prediction: 0% (34th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-28985
Weakness: CWE-407
Affected product: Libexpat Project Libexpat
Published: 2026-05-10
Last modified: 2026-06-30

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.

Frequently asked questions

What is 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.
How severe is CVE-2026-45186?: CVE-2026-45186 has a CVSS 3.x base score of 2.9, rated low severity. It is exploitable over local access with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability low.
Is CVE-2026-45186 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (34th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-45186?: CVE-2026-45186 affects Libexpat Project Libexpat. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-45186?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-45186 have an EU (EUVD) identifier?: Yes. CVE-2026-45186 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-28985.
When was CVE-2026-45186 published?: CVE-2026-45186 was published on 2026-05-10 and last updated on 2026-06-30.

References

Affected products (1)

cpe:2.3:a:libexpat_project:libexpat:*:*:*:*:*:*:*:*

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