CVE-2021-28164
MediumPublic exploitIn Eclipse Jetty 9.4.37.v20210219 to 9.4.38.v20210224, the default compliance mode allows requests with URIs that contain %2e or %2e%2e segments to access protected resources within the WEB-INF directory.
Published Jun 30, 2021 · Updated Aug 27, 2026 · Also known as DEBIAN-CVE-2021-28164, GHSA-v7ff-8wcx-gmc5, UBUNTU-CVE-2021-28164
Key Facts
Patch immediately- CVE-2021-28164 is a medium-severity vulnerability (CVSS 5.3 v3.1) affecting Jetty (Eclipse), Cloud Manager (Netapp), Element Plug-In For Vcenter Server (Netapp) and 22 more products.
- It is not listed in any known-exploited vulnerabilities catalog. Public exploit code is available.
- EPSS estimates a 82% probability of exploitation in the next 30 days.
- Fixed versions are available, including Jetty unspecified, jetty-annotations 9.4.42-3.9.1, jetty-annotations 9.4.43-1.2.
- Brandefense priority: patch immediately, because it is very likely to be exploited soon.
CVSS v3.1
5.3
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
EPSS (30-day exploit likelihood)
82%
Higher than 99.6% of all scored CVEs
Exploited in the wild
No known
Not in a known-exploited catalog
Public exploit code
Available
Proof-of-concept or weaponized module
Get the full CVE-2021-28164 brief as a PDF
Every affected product and fixed release, exploitation status and a first 24 hours response checklist, emailed within minutes.
Description
In Eclipse Jetty 9.4.37.v20210219 to 9.4.38.v20210224, 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.
Affected Products
112 affected entries in total| Product | Affected versions | Fixed in |
|---|---|---|
| JettyEclipse | 9.4.37-20210219, 9.4.38-20210224, >= 9.4.37.v20210219 | unspecified |
| Cloud ManagerNetapp | See advisory | n/a |
| Element Plug-In For Vcenter ServerNetapp | See advisory | n/a |
| E-Series Performance AnalyzerNetapp | See advisory | n/a |
| E-Series Santricity OS ControllerNetapp | See advisory | 11.70.1 |
Patched Releases
Jetty
unspecified
jetty-annotations
9.4.42-3.9.1, 9.4.43-1.2
jetty-ant
9.4.43-1.2
jetty-cdi
9.4.43-1.2
jetty-client
9.4.42-3.9.1, 9.4.43-1.2
jetty-continuation
9.4.42-3.9.1, 9.4.43-1.2
jetty-deploy
9.4.43-1.2
jetty-fcgi
9.4.43-1.2
jetty-http
9.4.42-3.9.1, 9.4.43-1.2
jetty-http-spi
9.4.43-1.2
jetty-io
9.4.42-3.9.1, 9.4.43-1.2
jetty-jaas
9.4.42-3.9.1, 9.4.43-1.2
jetty-javax-websocket-client-impl
9.4.42-3.9.1
jetty-javax-websocket-server-impl
9.4.42-3.9.1
jetty-jmx
9.4.42-3.9.1, 9.4.43-1.2
jetty-jndi
9.4.42-3.9.1, 9.4.43-1.2
jetty-jsp
9.4.42-3.9.1, 9.4.43-1.2
jetty-minimal
9.4.42-3.9.1
jetty-minimal-javadoc
9.4.42-3.9.1, 9.4.43-1.2
jetty-openid
9.4.42-3.9.1, 9.4.43-1.2
jetty-plus
9.4.42-3.9.1, 9.4.43-1.2
jetty-proxy
9.4.42-3.9.1, 9.4.43-1.2
jetty-quickstart
9.4.43-1.2
jetty-rewrite
9.4.43-1.2
jetty-security
9.4.42-3.9.1, 9.4.43-1.2
Timeline
Publicly disclosed
Jun 30, 2021
Last updated
Aug 27, 2026
Weakness Type
- CWE-200 Exposure of Sensitive Information to an Unauthorized Actor
- CWE-551 Incorrect Behavior Order: Authorization Before Parsing and Canonicalization
- CWE-863 Incorrect Authorization
References
- advisoryhttp://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-1968
- advisoryhttp://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-28163
- advisoryhttp://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-28164
- advisoryhttp://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-28165
- advisoryhttp://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-3449
FAQ
Common Questions.
In Eclipse Jetty 9.4.37.v20210219 to 9.4.38.v20210224, the default compliance mode allows requests with URIs that contain %2e or %2e%2e segments to access protected resources within the WEB-INF directory.
Affected: Jetty (Eclipse) versions 9.4.37-20210219, 9.4.38-20210224, >= 9.4.37.v20210219; Cloud Manager (Netapp); Element Plug-In For Vcenter Server (Netapp), among others. The full list is in the CVE brief.
It is not listed in any known-exploited vulnerabilities catalog.
No, it is not currently listed in the CISA Known Exploited Vulnerabilities catalog.
Public exploit code is available.
Fixed versions are available, including Jetty unspecified, jetty-annotations 9.4.42-3.9.1, jetty-annotations 9.4.43-1.2.
Brandefense priority: patch immediately, because it is very likely to be exploited soon.
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