CVE-2026-8466

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 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

0.38% probability of exploitation activity in the next 30 days.

EPSS percentile

Ranks above 31.2% 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:N/VI:N/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 2026-06-17.

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

2026-05-13 18:26Z3 MO AGO

Last updated

2026-05-14 04:30Z3 MO AGO

Reserved

2026-05-13

Assigning CNA

EEF

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:N/VI:N/VA:H/SC:N/SI:N/SA:N

Weaknesses

• CWE-770Allocation of Resources Without Limits or ThrottlingBase

Data version

5.2

Document digest

7304f3c69f81c8974c94cc7b2c393a87b76f8b844616aede5037cab13e1b6ddf

• cna.erlef.orghttps://cna.erlef.org/cves/CVE-2026-8466.htmlrelatedthird-party-advisory
• osv.devhttps://osv.dev/vulnerability/EEF-CVE-2026-8466related
• github.comhttps://github.com/ninenines/cowboy/commit/5c6a2061b41bb5771c4659fac7d5a822dca5bafbpatch