CVE-2026-56766

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

2.43% probability of exploitation activity in the next 30 days.

EPSS percentile

Equal to or higher than the score of 84.0% 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

Deferred. NVD last modified this record on 2026-10-25.

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

2026-06-25 18:01Z4 MO AGO

Last updated

2026-07-14 21:34Z3 MO AGO

Reserved

2026-06-22

Assigning CNA

VulnCheck

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-121Stack-based Buffer OverflowVariant
• CWE-120Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')Base

Data version

5.2

Document digest

ee1233c69a24046ecdc69bc9761625ae8bfb6fd5899a0304cd947170343ad58a

• github.comPatch Commithttps://github.com/vanhauser-thc/thc-hydra/commit/9cc84c20e75f5fef6bb1790bb9ada2afad2204e2patch
• www.vulncheck.comhttps://www.vulncheck.com/advisories/hydra-stack-buffer-overflow-in-ntlm-authentication-handlerthird-party-advisory