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Maven

GHSA-v7ff-8wcx-gmc5

MEDIUM

Authorization Before Parsing and Canonicalization in jetty

Also known asCVE-2021-28164
Published
Apr 6, 2021
Updated
Jul 8, 2026
Affected
1 pkg
Patched
1 / 1
Exploits
3 known

EPSS Exploitation Probability

via FIRST.org ↗
82.4%probability of exploitation in next 30 days
Very High Risk100th percentile0.00%
79.0%85.0%90.9%96.8%93.4%82.4%Jan 26May 26Jul 26

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.

Blast Radius

1 pkg affected
org.eclipse.jetty:jetty-webapp

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Maven packages — download data is not available via public APIs for these ecosystems.

Description

Release 9.4.37 introduced a more precise implementation of RFC3986 with regards to URI decoding, together with some new compliance modes to optionally allow support of some URI that may have ambiguous interpretation within the Servlet specified API methods behaviours. The default mode allowed % encoded . characters to be excluded for URI normalisation, which is correct by the RFC, but is not assumed by common Servlet implementations. The default compliance mode allows requests with URIs that contain %2e or %2e%2e segments to access protected resources within the WEB-INF directory. For example a request to /context/%2e/WEB-INF/web.xml can retrieve the web.xml file. This can reveal sensitive information regarding the implementation of a web application. Workarounds found by HttpCompliance mode RFC7230_NO_AMBIGUOUS_URIS can be enabled by updating start.d/http.ini to include: jetty.http.compliance=RFC7230_NO_AMBIGUOUS_URIS.

Affected Packages

1 total 1 fixed
EcosystemPackageVulnerable rangeFix
Mavenorg.eclipse.jetty:jetty-webapp9.4.37&&< 9.4.399.4.39
Exploits & PoCs
3

Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.

EDB-50438webappsjava

Jetty 9.4.37.v20210219 - Information Disclosure

by Mayank Deshmukh · Oct 22, 2021

Detection & mitigation playbook

Open-source dependency
  1. Detect

    Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.eclipse.jetty:jetty-webapp. 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.

  2. Fix

    Update org.eclipse.jetty:jetty-webapp to 9.4.39 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-v7ff-8wcx-gmc5 is resolved across your whole dependency graph.

  3. 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.

  4. How O3 protects you

    O3 pinpoints whether GHSA-v7ff-8wcx-gmc5 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 GHSA-v7ff-8wcx-gmc5. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

Release 9.4.37 introduced a more precise implementation of [RFC3986](https://tools.ietf.org/html/rfc3986#section-3.3) with regards to URI decoding, together with some new compliance modes to optionally allow support of some URI that may have ambiguous interpretation within the Servlet specified API methods behaviours. The default mode allowed % encoded . characters to be excluded for URI normalisation, which is correct by the RFC, but is not assumed by common Servlet implementations. The default compliance mode allows requests with URIs that contain `%2e` or `%2e%2e` segments to access prote
O3 Security · Impact-Aware SCA

Is GHSA-v7ff-8wcx-gmc5 in your dependencies?

O3 detects GHSA-v7ff-8wcx-gmc5 across Maven dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.