CVE-2026-66883

Exploitation

Public exploit code exists. CISA's assessment records a public proof of concept. That is not a report of exploitation in the wild.

SSVC decision

• ExploitationpocPublic proof-of-concept exploit code exists. Not a report of exploitation in the wild.
• 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

0.29% probability of exploitation activity in the next 30 days.

EPSS percentile

Ranks above 21.4% of scored records. A rank, not a probability.

NVD base score

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

NVD CVSS vector

CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:L/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

Awaiting Analysis. NVD last modified this record on 2026-08-04.

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

2026-08-04 11:46Z1 MO AGO

Last updated

2026-08-04 12:27Z1 MO AGO

Reserved

2026-07-28

Assigning CNA

EEF

Record state

PUBLISHED

Severity

Medium (CVSS 6.3)

CNA CVSS vector

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

Weaknesses

• CWE-178Improper Handling of Case SensitivityBase

Data version

5.2

Document digest

155efaeb0cba5aa09f0f114bc0daa3ca7d49efc9dcfec9ad915ed316903b1a24

• github.comhttps://github.com/erlef/oidcc_plug/security/advisories/GHSA-w5r8-m75h-98fcvendor-advisoryrelated
• cna.erlef.orghttps://cna.erlef.org/cves/CVE-2026-66883.htmlrelated
• osv.devhttps://osv.dev/vulnerability/EEF-CVE-2026-66883related
• github.comhttps://github.com/erlef/oidcc_plug/commit/f15e52c5750aaba701104b10ed96cfac063bd557patch