CVE-2026-66298

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.
• AutomatablenoAt least one step from reconnaissance to exploitation cannot be reliably automated.
• 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

0.17% probability of exploitation activity in the next 30 days.

EPSS percentile

Ranks above 6.5% of scored records. A rank, not a probability.

NVD base score

8.6 (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:A/VC:H/VI:H/VA:H/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

Analyzed. NVD last modified this record on 2026-08-10.

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

2026-08-05 19:44Z1 MO AGO

Last updated

2026-08-06 13:08Z29 DAYS AGO

Reserved

2026-07-24

Assigning CNA

EEF

Record state

PUBLISHED

Severity

High (CVSS 8.6)

CNA CVSS vector

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

Weaknesses

• CWE-346Origin Validation ErrorClass

Data version

5.2

Document digest

097293cb49536b894057e12cfb33a622c0ca289d27f5f5755e8b37966d87c848

• github.comhttps://github.com/livebook-dev/livebook/security/advisories/GHSA-68c2-prqg-x62gvendor-advisoryrelated
• cna.erlef.orghttps://cna.erlef.org/cves/CVE-2026-66298.htmlrelated
• osv.devhttps://osv.dev/vulnerability/EEF-CVE-2026-66298related
• github.comhttps://github.com/livebook-dev/livebook/commit/296318ffdfa6e5ed7b18ad8d5a5b2af90f3cd728patch
• github.comhttps://github.com/livebook-dev/livebook/commit/a552ce8f99ad348ea37061394dc950a0cebdb33epatch
• github.comhttps://github.com/livebook-dev/livebook/commit/5980e5c6b71036806b3bf54101eb1d6c0f50f19cpatch