CVE-2026-55559

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 ImpacttotalSuccessful exploitation gives total 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

Not scored by EPSS

EPSS percentile

Not scored by EPSS

NVD base score

9.8 (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:U/C:H/I:H/A:H

NVD analysis status

Received. NVD last modified this record on 2026-08-28.

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

2026-08-28 17:22Z12 HR AGO

Last updated

2026-08-28 19:58Z10 HR AGO

Reserved

2026-06-16

Assigning CNA

GitHub_M

Record state

PUBLISHED

Severity

Critical (CVSS 9.8)

CNA CVSS vector

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

Weaknesses

• CWE-94Improper Control of Generation of Code ('Code Injection')Base
• CWE-470Use of Externally-Controlled Input to Select Classes or Code ('Unsafe Reflection')Base
• CWE-1336Improper Neutralization of Special Elements Used in a Template EngineBase

Data version

5.2

Document digest

0561e8ea513f1fff187c6a0ce1856e430fc7d05b5cc1775ef390609b54132f1d

• github.comhttps://github.com/yamcs/yamcs/security/advisories/GHSA-73mf-m39p-wpm9x_refsource_CONFIRM
• github.comhttps://github.com/yamcs/yamcs/commit/549f295cf8c5496a5e799d6bec2432ef976c82aax_refsource_MISC
• github.comhttps://github.com/yamcs/yamcs/commit/7192da1c49bdf5ab1d72e579a47766a7c43e87c8x_refsource_MISC
• github.comhttps://github.com/yamcs/yamcs/releases/tag/yamcs-5.12.8x_refsource_MISC
• github.comhttps://github.com/yamcs/yamcs/releases/tag/yamcs-5.13.2x_refsource_MISC