Summary
oras-go blob upload vulnerable to credential forwarding via unvalidated Location header
oras-go follows a registry-controlled Location header during the monolithic blob upload flow and reuses the Authorization header from the initial POST request for the subsequent PUT request. If a malicious registry returns a cross-host Location, oras-go can send the caller's credentials to an attacker-controlled endpoint.
Affected Versions
tested: v2.6.0 (commit 03243809936cce826494b5506f724c6dc11115b1, as-of 2026-01-24)
range: unknown; likely affects earlier v2.x releases that include the same upload flow
Affected Component
registry/remote/repository.go:878-916(blobStore.completePushAfterInitialPost)
Reproduction
Attachments include poc.zip with a local-only harness (no real registry required). It runs a fake registry server that returns a cross-host Location and a second server that records whether it received Authorization.
unzip -q -o poc.zip -d /tmp/poc
cd /tmp/poc/poc-F-ORAS-LOCATION-UPLOAD-001
make canonical
make control
references
- security policy: https://github.com/oras-project/oras-go/security/policy
- vulnerable code:
registry/remote/repository.go(seeblobStore.completePushAfterInitialPost)
Impact
Credential leak to an attacker-controlled endpoint and client-side ssrf to a cross-host target.
Untrusted input controls the target URL of a server-initiated request, which may reach internal services not otherwise accessible from outside. Typical impact: access to internal metadata services, internal APIs, or cloud credentials.
CVE-2026-50151 has a CVSS score of 7.5 (High). The vector is network-reachable, no privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (2.6.1); upgrading removes the vulnerable code path.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
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- validate
Locationbefore uploading (scheme + hostname + effective port) against the original request, or require an explicit opt-in allowlist for cross-host upload urls - never forward
Authorizationwhen the upload target changes host or scheme
Frequently Asked Questions
- What is CVE-2026-50151? CVE-2026-50151 is a high-severity server-side request forgery (SSRF) vulnerability in oras.land/oras-go/v2 (go), affecting versions < 2.6.1. It is fixed in 2.6.1. Untrusted input controls the target URL of a server-initiated request, which may reach internal services not otherwise accessible from outside.
- How severe is CVE-2026-50151? CVE-2026-50151 has a CVSS score of 7.5 (High). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
- Which versions of oras.land/oras-go/v2 are affected by CVE-2026-50151? oras.land/oras-go/v2 (go) versions < 2.6.1 is affected.
- Is there a fix for CVE-2026-50151? Yes. CVE-2026-50151 is fixed in 2.6.1. Upgrade to this version or later.
- Is CVE-2026-50151 exploitable, and should I be worried? Whether CVE-2026-50151 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether CVE-2026-50151 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix CVE-2026-50151? Upgrade
oras.land/oras-go/v2to 2.6.1 or later.