CVE-2026-55599

Exploitation

Public exploit code exists. CISA's assessment records a public proof of concept. That is not a report of exploitation in the wild.

SSVC decision

• ExploitationpocPublic proof-of-concept exploit code exists. Not a report of exploitation in the wild.
• 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

0.21% probability of exploitation activity in the next 30 days.

EPSS percentile

Equal to or higher than the score of 11.4% of scored records. A rank, not a probability.

NVD base score

5.8 (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:C/C:L/I:N/A:N

NVD analysis status

Analyzed. NVD last modified this record on 2026-06-26.

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

2026-06-22 20:00Z4 MO AGO

Last updated

2026-06-23 16:12Z4 MO AGO

Reserved

2026-06-16

Assigning CNA

GitHub_M

Record state

PUBLISHED

Severity

Medium (CVSS 5.8)

CNA CVSS vector

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

Weaknesses

• CWE-918Server-Side Request Forgery (SSRF)Base

Data version

5.2

Document digest

fe138e1db58756e20f887fb3cc7a006620ec54d599e8c1d0631bd5b60e9fa7be

• github.comhttps://github.com/phpseclib/phpseclib/security/advisories/GHSA-m557-wrgg-6rp4x_refsource_CONFIRM