CVE-2025-66559

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 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

0.31% probability of exploitation activity in the next 30 days.

EPSS percentile

Equal to or higher than the score of 23.8% of scored records. A rank, not a probability.

NVD base score

8.0 (CVSS v4.0), scored by the NVD independently of the CNA.

NVD CVSS vector

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:U/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

NVD analysis status

Deferred. NVD last modified this record on 2026-10-18.

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

2025-12-04 22:23Z10 MO AGO

Last updated

2025-12-05 17:29Z10 MO AGO

Reserved

2025-12-04

Assigning CNA

GitHub_M

Record state

PUBLISHED

Severity

High (CVSS 8.0)

CNA CVSS vector

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:U

Weaknesses

• CWE-129Improper Validation of Array IndexVariant

Data version

5.2

Document digest

3978e32d593c50c81fed1ea52961de72bc307ebfb1a26d16525825a881b10a15

• github.comhttps://github.com/taikoxyz/taiko-mono/security/advisories/GHSA-5mxh-r33p-6h5xx_refsource_CONFIRM
• github.comhttps://github.com/taikoxyz/taiko-mono/commit/379f5cb4ffe9e1945563ab2c7740bc9f4ea004d8x_refsource_MISC