Incorrect Authorization Affecting github.com/zalando/skipper/filters/openpolicyagent/opaserveresponse package, versions <0.27.35
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Start learning- Snyk IDSNYK-GOLANG-GITHUBCOMZALANDOSKIPPERFILTERSOPENPOLICYAGENTOPASERVERESPONSE-19883924
- published17 Sept 2026
- disclosed16 Sept 2026
- creditPig-Tail
Introduced: 16 Sep 2026
NewCVE-2026-86043 Â (opens in a new tab)How to fix?
Upgrade github.com/zalando/skipper/filters/openpolicyagent/opaserveresponse to version 0.27.35 or higher.
Overview
Affected versions of this package are vulnerable to Incorrect Authorization through ExtractHttpBodyOptionally in filters/openpolicyagent/openpolicyagent.go and AdaptToExtAuthRequest in filters/openpolicyagent/internal/envoy/skipperadapter.go. An attacker can get an oversized request body authorized and forwarded to the upstream service by sending the request with chunked framing or over HTTP/2 so no Content-Length is present. In that path, Skipper truncates the body for OPA inspection, but the body-truncation signal is not carried into the ext-authz request, so policies that gate on input.truncated_body evaluate as if the body were complete. This lets a remote client bypass body-based access control and send content that the policy was meant to reject, exposing protected actions or data to the upstream application.