Vulnerability · CVE-2021-28169
Eclipse Jetty ConcatServlet Vulnerability
Published Aug 19, 2022 · corrected/updated Aug 19, 2022 · eclipse jetty · evidence confidence very high
For Eclipse Jetty versions <= 9.4.40, <= 10.0.2, <= 11.0.2, it is possible for requests to the ConcatServlet with a doubly encoded path to access protected resources within the WEB-INF directory. For example a request to can retrieve the web.xml file. This can reveal sensitive information regarding the implementation of a web application.
Grounded briefings
Catalog interpretations for three audiences. Each brief cites ingested metadata and the original advisories below. They are not independent research and they do not invent exploit steps.
Executive
CVE-2021-28169 is a unknown public vulnerability record for eclipse jetty. CISA lists it as known exploited. Published remediation guidance: Apply remediations or mitigations per vendor instructions or discontinue use of the product if remediation or mitigations are unavailable. This summary is a catalog interpretation of the ingested metadata and cites the original advisories below.
System administrator
Identify whether eclipse jetty is in your estate, then compare installed versions with the affected ranges. Affected packages or ranges on record: eclipse jetty. Published remediation guidance: Apply remediations or mitigations per vendor instructions or discontinue use of the product if remediation or mitigations are unavailable. Prefer the vendor or distribution advisory linked in Sources before changing production systems. This is a catalog interpretation, not a runbook.
Security analyst
Signals on file: no CVSS/EPSS yet. CISA lists it as known exploited. Sources contributing to this record: vulncheck_kev. Public exploit references, when present, are outbound links only and are not proof of active exploitation. This is a catalog interpretation of stored metadata.
Exploitation and remediation
Exploitation evidence
Confirmed in CISA KEV since Aug 19, 2022. Listed in CISA KEV and VulnCheck KEV.
Patch and remediation
Apply remediations or mitigations per vendor instructions or discontinue use of the product if remediation or mitigations are unavailable.
Safe detection guidance
Compare installed versions with the affected ranges below and verify the advisory from the original publisher. This site stores metadata and outbound links only; it does not ship exploit code or proof-of-concept payloads.
Code
The project this record applies to. Exploit listings stay in References.
No public source repository is identified for this product.
Timeline
Detection, updates, and resolution for this record.
Aug 19, 2022 · VulnCheck KEV
Detected
For Eclipse Jetty versions <= 9.4.40, <= 10.0.2, <= 11.0.2, it is possible for requests to the ConcatServlet with a doubly encoded path to access protected resources within the WEB-INF directory. For example a request to can retrieve the web.xml file. This can reveal sensitive information regarding the implementation of a web application.
Aug 19, 2022 · CISA KEV
Known exploited
Apply remediations or mitigations per vendor instructions or discontinue use of the product if remediation or mitigations are unavailable.
Affected
- vendor eclipse jettyversion unspecified
Sources
- VulnCheck KEVConfirmed exploitationCVE-2021-28169
For Eclipse Jetty versions <= 9.4.40, <= 10.0.2, <= 11.0.2, it is possible for requests to the ConcatServlet with a doubly encoded path to access protected resources within the WEB-INF directory. For example a request to can retrieve the web.xml file. This can reveal sensitive in
vulncheck.com