Improper input validation in Zalando Skipper
CVE-2026-65604
Skipper contains an incomplete fix for CVE-2026-50197 in which oversized request bodies bypass Open Policy Agent (OPA) deny-on-presence Rego policies. When a request body exceeds the configured maxBodyBytes limit, Skipper forwards the full payload to the upstream service while OPA evaluates against an empty parsed_body, so policies that deny requests based on body content are not enforced and forbidden actions proceed. No fixed version is available; v0.27.26 adds documentation guidance only.
Vulnerability class: Drupalgeddon 2 (CVE-2018-7600)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 8.2 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N.
EPSS exploit prediction
EPSS: 0.004 (32.0th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 32nd percentile — 32.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: 0.000
Affected products
Weakness classification (CWE)
References
- github.com/zalando/skipper/security/advisories/GHSA-8qqm-fp2q-v734 (vendor-advisory)
- www.vulncheck.com/advisories/skipper-incomplete-fix-for-cve-2026-50197-policy-b… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-65604?
- CVE-2026-65604 is a high-severity vulnerability in Zalando Skipper, classified under Improper Input Validation. CVSS score: 8.2/10. Published 2026-07-23.
- How severe is CVE-2026-65604?
- High severity. CVSS v3 base score is 8.2 out of 10.