How severe is CVE-2026-56132?

CVE-2026-56132 has a CVSS 3.x base score of 6.9, rated medium severity. It is exploitable over local access with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability low.

Is CVE-2026-56132 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (1st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-56132?

CVE-2026-56132 affects Libexpat Project Libexpat. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-56132?

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

Does CVE-2026-56132 have an EU (EUVD) identifier?

Yes. CVE-2026-56132 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-37977.

When was CVE-2026-56132 published?

CVE-2026-56132 was published on 2026-06-19 and last updated on 2026-06-23.

CVE-2026-56132

CVE-2026-56132 is a medium-severity vulnerability in Libexpat Project Libexpat with a CVSS 3.x base score of 6.9. 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-821.

Key facts

Severity: Medium (CVSS 3.x base score 6.9)
EPSS exploit prediction: 0% (1st percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-37977
Weakness: CWE-821
Affected product: Libexpat Project Libexpat
Published: 2026-06-19
Last modified: 2026-06-23

Description

In libexpat before 2.8.2, there is a heap-based buffer overflow in doProlog in xmlparse.c because scaffold backing array reallocation is mishandled when there is data-structure sharing across parsers.

Frequently asked questions

What is CVE-2026-56132?: In libexpat before 2.8.2, there is a heap-based buffer overflow in doProlog in xmlparse.c because scaffold backing array reallocation is mishandled when there is data-structure sharing across parsers.
How severe is CVE-2026-56132?: CVE-2026-56132 has a CVSS 3.x base score of 6.9, rated medium severity. It is exploitable over local access with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability low.
Is CVE-2026-56132 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (1st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-56132?: CVE-2026-56132 affects Libexpat Project Libexpat. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-56132?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-56132 have an EU (EUVD) identifier?: Yes. CVE-2026-56132 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-37977.
When was CVE-2026-56132 published?: CVE-2026-56132 was published on 2026-06-19 and last updated on 2026-06-23.

References

https://github.com/libexpat/libexpat/pull/1272

Affected products (1)

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

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