CVE-2025-66566

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

0.60% probability of exploitation activity in the next 30 days.

EPSS percentile

Equal to or higher than the score of 48.7% of scored records. A rank, not a probability.

NVD base score

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

NVD CVSS vector

CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/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 2026-09-25.

Red Hat severity

Important. Red Hat's rating for its own products, not a CVSS rating.

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

2025-12-05 18:10Z10 MO AGO

Last updated

2025-12-05 18:27Z10 MO AGO

Reserved

2025-12-04

Assigning CNA

GitHub_M

Record state

PUBLISHED

Severity

High (CVSS 8.2)

CNA CVSS vector

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

Weaknesses

• CWE-201Insertion of Sensitive Information Into Sent DataBase
• CWE-908Use of Uninitialized ResourceBase

Data version

5.2

Document digest

f632eba50bb04e66e404f0fba3f535bfba0d8dd14f670ad57ac74ea83ab42f75

• github.comhttps://github.com/yawkat/lz4-java/security/advisories/GHSA-cmp6-m4wj-q63qx_refsource_CONFIRM
• github.comhttps://github.com/yawkat/lz4-java/commit/33d180cb70c4d93c80fb0dc3ab3002f457e93840x_refsource_MISC