CVE-2021-28169
Exposure of Sensitive Information to an Unauthorized Actor
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
Description
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 `/concat?/%2557EB-INF/web.xml` can retrieve the web.xml file. This can reveal sensitive information regarding the implementation of a web application.
Official description from the CVE record, published by eclipse. Copyright © 1999-2026 The MITRE Corporation. See /security/cve/legal for the CVE license. View the record on cve.org
Key data
CVSS 3.1 Medium 5.3
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
Attack vector: Network
The vulnerable component can be reached over a network, possibly from the Internet.
Attack complexity: Low
No special conditions are needed. The attack can be repeated at will.
Privileges required: None
No account or privileges are needed.
User interaction: None
No action from any user is needed.
Scope: Unchanged
The impact stays within the vulnerable component.
Confidentiality impact: Low
Limited effect on the secrecy of data.
Integrity impact: None
No effect on the trustworthiness of data.
Availability impact: None
No effect on availability.
| Metric | Value | What it means |
|---|---|---|
| Attack vector | Network | The vulnerable component can be reached over a network, possibly from the Internet. |
| Attack complexity | Low | No special conditions are needed. The attack can be repeated at will. |
| Privileges required | None | No account or privileges are needed. |
| User interaction | None | No action from any user is needed. |
| Scope | Unchanged | The impact stays within the vulnerable component. |
| Confidentiality impact | Low | Limited effect on the secrecy of data. |
| Integrity impact | None | No effect on the trustworthiness of data. |
| Availability impact | None | No effect on availability. |
CVSS is owned and managed by FIRST.Org, Inc. (FIRST) and is used by permission. Each CVSS score on this site is shown together with its vector string, as published in the CVE record by the source named next to it. Learn more at first.org/cvss.
EPSS
- Score
- 0.78480 (78.5% probability)
- Percentile
- 99.6%
- Scores of
- Nov 10, 2026
- Model
- v2026.06.15
Weakness (CWE)
- CWE-200Exposure of Sensitive Information to an Unauthorized Actor
Affected products
Eclipse Jetty
- affected: unspecified up to 9.4.40
- affected: unspecified up to 10.0.2
- affected: unspecified up to 11.0.2
References
- github.com/eclipse/jetty.project/security/advisories/GHSA-g…
- [kafka-users] 20210617 vulnerabilities (lists.apache.org)mailing-list
- [debian-lts-announce] 20210617 [SECURITY] [DLA 2688-1] jetty9 security update (lists.debian.org)mailing-list
- [kafka-jira] 20210623 [GitHub] [kafka] dongjinleekr opened a new pull request #10919: KAFKA-12985: CVE-2021-28169 - Upgrade jetty to 9.4.41 (lists.apache.org)mailing-list
- [kafka-dev] 20210623 [jira] [Created] (KAFKA-12985) CVE-2021-28169 - Upgrade jetty to 9.4.41 (lists.apache.org)mailing-list
- [kafka-jira] 20210623 [jira] [Created] (KAFKA-12985) CVE-2021-28169 - Upgrade jetty to 9.4.41 (lists.apache.org)mailing-list
- [kafka-jira] 20210704 [GitHub] [kafka] ijuma commented on pull request #10919: KAFKA-12985: CVE-2021-28169 - Upgrade jetty to 9.4.42 (lists.apache.org)mailing-list
- [kafka-jira] 20210704 [GitHub] [kafka] ijuma merged pull request #10919: KAFKA-12985: CVE-2021-28169 - Upgrade jetty to 9.4.42 (lists.apache.org)mailing-list
- [kafka-dev] 20210722 [jira] [Resolved] (KAFKA-12985) CVE-2021-28169 - Upgrade jetty to 9.4.41 (lists.apache.org)mailing-list
- [kafka-jira] 20210722 [jira] [Updated] (KAFKA-12985) CVE-2021-28169 - Upgrade jetty to 9.4.42 (lists.apache.org)mailing-list
- [kafka-jira] 20210722 [jira] [Resolved] (KAFKA-12985) CVE-2021-28169 - Upgrade jetty to 9.4.41 (lists.apache.org)mailing-list
- DSA-4949 (debian.org)vendor-advisory
- [zookeeper-issues] 20210928 [jira] [Updated] (ZOOKEEPER-4390) CVE-2021-28169 - Upgrade jetty to 9.4.42 (lists.apache.org)mailing-list
- [zookeeper-issues] 20210928 [jira] [Created] (ZOOKEEPER-4390) CVE-2021-28169 - Upgrade jetty to 9.4.42 (lists.apache.org)mailing-list
- [zookeeper-issues] 20210928 [jira] [Updated] (ZOOKEEPER-4390) CVE-2021-28169 , - Upgrade jetty to 9.4.42 (lists.apache.org)mailing-list
- [zookeeper-issues] 20210928 [jira] [Updated] (ZOOKEEPER-4390) CVE-2021-28169 , CVE-2021-28163, - Upgrade jetty to 9.4.42 (lists.apache.org)mailing-list
- [zookeeper-dev] 20210928 [jira] [Created] (ZOOKEEPER-4390) CVE-2021-28169 - Upgrade jetty to 9.4.42 (lists.apache.org)mailing-list
- [zookeeper-issues] 20210928 [jira] [Updated] (ZOOKEEPER-4390) CVE-2021-28169 , CVE-2021-28163, CVE-2021-34428- Upgrade jetty to 9.4.42 (lists.apache.org)mailing-list
- oracle.com/security-alerts/cpuoct2021.html
- lists.apache.org/thread.html/r8a1a332899a1f92c8118b0895b144…
- lists.apache.org/thread.html/rbefa055282d52d6b58d29a79fbb0b…
- security.netapp.com/advisory/ntap-20210727-0009
- oracle.com/security-alerts/cpujan2022.html
- oracle.com/security-alerts/cpuapr2022.html
Timeline
- ID reserved
- Record published
- Record last updated
Look up another CVE
About CubePath
Data from the CVE Program (MITRE), CISA KEV and FIRST EPSS. CVSS is owned by FIRST and used by permission. Not affiliated with or endorsed by MITRE, CISA or FIRST. Data as of Nov 10, 2026, 19:52 UTC. Sources and licenses