CVE-2021-28169

MEDIUMNVD 5.35.3—
EchelonGraph scoreMEDIUM confidence

This medium-severity CVE scores 5.3 under NVD CVSS v3. EPSS exploit probability: 78.5%, top 0% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: epss, nvd
Trending — 3 sources updated this weekElevated
5.3
EchelonGraph verdictPatch this weekExploitation is likely or a public exploit exists.
  • High exploitation likelihood — EPSS 78%
CISA-KEV: Not listedEPSS: 78%CVSS: 5.3Exploit: NoneExposed: 0

A fix is available — apply it.

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.

CVSS v3
5.3
EG Score
5.3(medium)
EPSS
99.5%
KEV
Not listed

Published

June 9, 2021

Last Modified

November 21, 2024

References (48)

Vendor Advisories for CVE-2021-28169(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Patch Availability(4)

Vendor / EcosystemFixed in / PatchReleasedSource
redhatjetty2022-10-27redhat
redhatpatch2021-11-23redhat
redhatjenkins-0:2.289.3.1630554997-1.el82021-10-18redhat
redhatjetty-server2021-09-30redhat

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Affected Packages

(1 across 1 ecosystem)
Maven(1)
PackageVulnerable rangeFixed inDependents
org.eclipse.jetty:jetty-servlets11.0.0, 11.0.1, 11.0.211.0.3—

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Additional Vendor Advisories

(5)

Vendors that published advisories for this CVE beyond the curated set above. Broader coverage but minimal per-row detail — click through for the original advisory.

Data Freshness Timeline

(refreshed 8× in last 7d / 23× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-07-22 22:46 UTCEG score recompute▼ 3.70
  2. 2026-07-22 14:06 UTCEPSS rescore
  3. 2026-07-22 14:06 UTCEPSS rescore
  4. 2026-07-21 15:22 UTCEPSS rescore
  5. 2026-07-21 15:22 UTCEPSS rescore
  6. 2026-07-19 02:27 UTCEPSS rescore
  7. 2026-07-19 02:27 UTCEPSS rescore
  8. 2026-07-18 18:59 UTCOSV refresh
  9. 2026-07-15 16:55 UTCEPSS rescore
  10. 2026-07-15 16:55 UTCEPSS rescore
  11. 2026-07-13 22:27 UTCEPSS rescore
  12. 2026-07-13 22:27 UTCEPSS rescore
  13. 2026-07-11 08:25 UTCEPSS rescore
  14. 2026-07-11 08:25 UTCEPSS rescore
  15. 2026-07-08 15:12 UTCEPSS rescore
  16. 2026-07-02 16:57 UTCEPSS rescore
  17. 2026-07-01 01:48 UTCOSV refresh
  18. 2026-06-30 23:20 UTCEPSS rescore
  19. 2026-06-30 23:20 UTCEPSS rescore
  20. 2026-06-25 13:48 UTCEPSS rescore
  21. 2026-06-25 13:48 UTCEPSS rescore
  22. 2026-06-23 21:31 UTCEPSS rescore
  23. 2026-06-23 21:31 UTCEPSS rescore
  24. 2026-06-22 14:24 UTCEPSS rescore
  25. 2026-06-22 14:24 UTCEPSS rescore
Show 26 more
  1. 2026-06-21 14:55 UTCEPSS rescore
  2. 2026-06-21 14:54 UTCEPSS rescore
  3. 2026-06-17 17:51 UTCEPSS rescore
  4. 2026-06-16 17:51 UTCEPSS rescore
  5. 2026-06-15 17:46 UTCEPSS rescore
  6. 2026-06-13 22:58 UTCEPSS rescore
  7. 2026-06-13 22:58 UTCEPSS rescore
  8. 2026-06-13 04:13 UTCOSV refresh
  9. 2026-06-10 22:16 UTCEPSS rescore
  10. 2026-06-10 13:20 UTCEPSS rescore
  11. 2026-06-08 14:15 UTCEPSS rescore
  12. 2026-06-05 22:45 UTCEPSS rescore
  13. 2026-06-05 22:45 UTCEPSS rescore
  14. 2026-06-05 06:09 UTCEPSS rescore
  15. 2026-06-05 06:09 UTCEPSS rescore
  16. 2026-06-02 20:11 UTCEPSS rescore
  17. 2026-06-02 20:11 UTCEPSS rescore
  18. 2026-06-02 20:11 UTCEPSS rescore
  19. 2026-05-31 00:15 UTCEPSS rescore
  20. 2026-05-28 13:43 UTCEPSS rescore
  21. 2026-05-28 13:43 UTCEPSS rescore
  22. 2026-05-27 13:39 UTCEPSS rescore
  23. 2026-05-27 13:39 UTCEPSS rescore
  24. 2026-05-26 15:17 UTCEG score recompute
  25. 2026-05-26 15:17 UTCVendor advisory
  26. 2026-05-23 14:41 UTCOSV refresh

Publicly available exploits

(1 reference)

Working exploit code is in the public domain. Defenders should treat patch urgency accordingly — public PoCs typically lead to mass-exploitation within 24-72 hours.

  • Nucleihttp/cves/2021/CVE-2021-28169.yaml
    First seen Jan 1, 2021

    Eclipse Jetty ConcatServlet - Information Disclosure

    Open source ↗

Related CVEs(same vendor + same CWE)

Frequently asked(5)

What is CVE-2021-28169?
CVE-2021-28169 is a medium vulnerability published on June 9, 2021. 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…
When was CVE-2021-28169 disclosed?
CVE-2021-28169 was first published in the National Vulnerability Database on June 9, 2021, with the most recent update on November 21, 2024. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2021-28169 actively exploited?
CVE-2021-28169 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 99.5% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2021-28169?
CVE-2021-28169 has a CVSS v3 base score of 5.3 (NVD).
How do I remediate CVE-2021-28169?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2021-28169, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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