CVE-2026-55213

Exploitation

Assessed, none found. CISA's assessment recorded neither public exploit code nor evidence of exploitation when it was made.

SSVC decision

• ExploitationnoneCISA recorded no public exploit code and no evidence of exploitation.
• AutomatableyesAn attacker can reliably automate reconnaissance through exploitation, so this scales.
• Technical ImpactpartialSuccessful exploitation gives limited control of the vulnerable component.

CISA publishes the decision points, not a final SSVC decision. The decision also depends on mission and well-being impact, which is a property of your deployment rather than of the vulnerability.

EPSS probability

0.48% probability of exploitation activity in the next 30 days.

EPSS percentile

Equal to or higher than the score of 41.6% of scored records. A rank, not a probability.

NVD base score

7.5 (CVSS v3.x), scored by the NVD independently of the CNA.

NVD CVSS vector

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

NVD analysis status

Awaiting Analysis. NVD last modified this record on 2026-07-13.

Red Hat severity

No Red Hat rating. Red Hat rates the CVEs that affect its products.

Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.

Published

2026-07-10 20:49Z3 MO AGO

Last updated

2026-07-13 14:14Z3 MO AGO

Reserved

2026-06-16

Assigning CNA

GitHub_M

Record state

PUBLISHED

Severity

High (CVSS 7.5)

CNA CVSS vector

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

Weaknesses

• CWE-789Memory Allocation with Excessive Size ValueVariant

Data version

5.2

Document digest

8a741a5d538e50fd1985376e5e83b880397b563a9bcad4bc4d49b9f1898681d8

• github.comhttps://github.com/h2o/h2o/security/advisories/GHSA-432c-8xmj-frmqx_refsource_CONFIRM
• github.comhttps://github.com/h2o/h2o/commit/edd7a120bfc4af11ac0cbebce2a43cc1f93f9af1x_refsource_MISC