CVE-2026-56857

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

0.55% probability of exploitation activity in the next 30 days.

EPSS percentile

Equal to or higher than the score of 45.9% of scored records. A rank, not a probability.

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

Awaiting Analysis. NVD last modified this record on 2026-10-09.

Red Hat severity

Low. 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

2026-10-08 22:53Z20 DAYS AGO

Last updated

2026-10-09 15:36Z19 DAYS AGO

Reserved

2026-06-23

Assigning CNA

Go

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-1386Insecure Operation on Windows Junction / Mount PointBase
• CWE-59Improper Link Resolution Before File Access ('Link Following')Base

Data version

5.2

Document digest

67d05ae9133bbd431b8a7c678171d14bd9d87a6bccad2f7e3b43fd7499cc53af

• go.devhttps://go.dev/cl/847305
• go.devhttps://go.dev/issue/81739
• groups.google.comhttps://groups.google.com/g/golang-announce/c/U2fTuyDJznI
• pkg.go.devhttps://pkg.go.dev/vuln/GO-2026-6604