CVE-2026-50197
Fix: zalando/skipper@3152f3bCVE-2026-50197 is a CWE-444 vulnerability in github.com/zalando/skipper. O3 Security confirms whether CVE-2026-50197 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Skipper: opaAuthorizeRequestWithBody filter bypasses OPA policy on Transfer-Encoding: chunked / HTTP/2 requests
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-50197.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
Real-World Exposure
github.com/zalando/skipperReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.
Description
Skipper is an HTTP router and reverse proxy for service composition. Prior to 0.26.10, zalando/skipper's OpenPolicyAgent integration silently bypasses request-body inspection on HTTP/1.1 Transfer-Encoding: chunked and HTTP/2 requests that omit the content-length pseudo-header, because the opaAuthorizeRequestWithBody filter and OpenPolicyAgentInstance.ExtractHttpBodyOptionally in filters/openpolicyagent/openpolicyagent.go produce an empty raw_body and input.parsed_body while the upstream service receives the full attacker-controlled body. This issue is fixed in version 0.26.10.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/zalando/skipper | all versions | 0.26.10 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/zalando/skipper. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update github.com/zalando/skipper to 0.26.10 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-50197 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether CVE-2026-50197 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2026-50197. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-50197 in your dependencies?
O3 detects CVE-2026-50197 across Go dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.