CVE-2019-17638

CRITICALNVD 9.49.4
EchelonGraph scoreMEDIUM confidence

This critical-severity CVE scores 9.4 under NVD CVSS v3. EPSS exploit probability: 30.9%, top 3% 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
Elevated
9.4
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS: 11%CVSS: 9.4Exploit: NoneExposed: 0

A fix is available — apply it.

In Eclipse Jetty, versions 9.4.27.v20200227 to 9.4.29.v20200521, in case of too large response headers, Jetty throws an exception to produce an HTTP 431 error. When this happens, the ByteBuffer containing the HTTP response headers is released back to the ByteBufferPool twice. Because of this double release, two threads can acquire the same ByteBuffer from the pool and while thread1 is about to use the ByteBuffer to write response1 data, thread2 fills the ByteBuffer with other data. Thread1 then proceeds to write the buffer that now contains different data. This results in client1, which issued request1 seeing data from another request or response which could contain sensitive data belonging to client2 (HTTP session ids, authentication credentials, etc.). If the Jetty version cannot be upgraded, the vulnerability can be significantly reduced by configuring a responseHeaderSize significantly larger than the requestHeaderSize (12KB responseHeaderSize and 8KB requestHeaderSize).

CVSS v3
9.4
EG Score
9.4(medium)
EPSS
95.4%
KEV
Not listed

Published

July 9, 2020

Last Modified

November 21, 2024

References (34)

Vendor Advisories for CVE-2019-17638(1)

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

Patch Availability(5)

Vendor / EcosystemFixed in / PatchReleasedSource
redhatjetty2020-12-16redhat
redhatjenkins-0:2.235.5.1600415953-1.el72020-10-22redhat
redhatopenshift4/ose-jenkins:v4.4.0-202009260441.p02020-10-13redhat
redhatjenkins-0:2.235.5.1600414805-1.el72020-09-30redhat
redhatjenkins-0:2.235.5.1600415514-1.el72020-09-23redhat

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-server9.4.27.v20200227, 9.4.28.v20200408, 9.4.29.v202005219.4.30.v20200611

Weakness Classification(2)

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

Additional Vendor Advisories

(4)

Data Freshness Timeline

(refreshed 9× in last 7d / 37× 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. 2026-07-11 08:24 UTCEPSS rescore
  2. 2026-07-11 08:24 UTCEPSS rescore
  3. 2026-07-09 19:06 UTCEPSS rescore
  4. 2026-07-08 15:11 UTCEPSS rescore
  5. 2026-07-07 13:43 UTCEPSS rescore
  6. 2026-07-06 16:25 UTCEPSS rescore
  7. 2026-07-06 16:25 UTCEPSS rescore
  8. 2026-07-06 02:20 UTCEPSS rescore
  9. 2026-07-05 02:27 UTCEPSS rescore
  10. 2026-07-04 06:28 UTCEPSS rescore
  11. 2026-07-01 15:03 UTCOSV refresh
  12. 2026-07-01 15:03 UTCEPSS rescore
  13. 2026-07-01 15:03 UTCEPSS rescore
  14. 2026-06-30 23:20 UTCEPSS rescore
  15. 2026-06-29 14:03 UTCEPSS rescore
  16. 2026-06-28 14:04 UTCEPSS rescore
  17. 2026-06-28 04:54 UTCEPSS rescore
  18. 2026-06-28 04:54 UTCEPSS rescore
  19. 2026-06-27 03:06 UTCEPSS rescore
  20. 2026-06-25 13:47 UTCEPSS rescore
  21. 2026-06-25 13:47 UTCEPSS rescore
  22. 2026-06-24 14:03 UTCEPSS rescore
  23. 2026-06-24 14:03 UTCEPSS rescore
  24. 2026-06-23 21:31 UTCEPSS rescore
  25. 2026-06-23 21:30 UTCEPSS rescore
Show 34 more
  1. 2026-06-22 14:23 UTCEPSS rescore
  2. 2026-06-21 14:54 UTCEPSS rescore
  3. 2026-06-21 14:54 UTCEPSS rescore
  4. 2026-06-18 17:50 UTCEPSS rescore
  5. 2026-06-17 17:50 UTCEPSS rescore
  6. 2026-06-16 17:50 UTCEPSS rescore
  7. 2026-06-15 17:45 UTCEPSS rescore
  8. 2026-06-14 23:15 UTCEPSS rescore
  9. 2026-06-14 23:15 UTCEPSS rescore
  10. 2026-06-13 23:43 UTCOSV refresh
  11. 2026-06-13 22:58 UTCEPSS rescore
  12. 2026-06-12 23:09 UTCEPSS rescore
  13. 2026-06-11 13:58 UTCEPSS rescore
  14. 2026-06-10 22:16 UTCEPSS rescore
  15. 2026-06-10 13:19 UTCEPSS rescore
  16. 2026-06-06 13:45 UTCEPSS rescore
  17. 2026-06-06 13:45 UTCEPSS rescore
  18. 2026-06-05 22:45 UTCEPSS rescore
  19. 2026-06-05 22:45 UTCEPSS rescore
  20. 2026-06-04 13:10 UTCEPSS rescore
  21. 2026-06-04 13:10 UTCEPSS rescore
  22. 2026-06-02 20:11 UTCEPSS rescore
  23. 2026-06-02 20:11 UTCEPSS rescore
  24. 2026-06-01 13:50 UTCEPSS rescore
  25. 2026-06-01 13:50 UTCEPSS rescore
  26. 2026-05-31 22:29 UTCEPSS rescore
  27. 2026-05-31 22:29 UTCEPSS rescore
  28. 2026-05-31 00:14 UTCEPSS rescore
  29. 2026-05-31 00:14 UTCEPSS rescore
  30. 2026-05-29 13:42 UTCEPSS rescore
  31. 2026-05-28 13:43 UTCEPSS rescore
  32. 2026-05-27 13:38 UTCEPSS rescore
  33. 2026-05-27 01:31 UTCEG score recompute
  34. 2026-05-27 01:31 UTCVendor advisory

Frequently asked(5)

What is CVE-2019-17638?
CVE-2019-17638 is a critical vulnerability published on July 9, 2020. In Eclipse Jetty, versions 9.4.27.v20200227 to 9.4.29.v20200521, in case of too large response headers, Jetty throws an exception to produce an HTTP 431 error. When this happens, the ByteBuffer containing the HTTP response headers is released back to the ByteBufferPool twice. Because of this double…
When was CVE-2019-17638 disclosed?
CVE-2019-17638 was first published in the National Vulnerability Database on July 9, 2020, 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-2019-17638 actively exploited?
CVE-2019-17638 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 95.4% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2019-17638?
CVE-2019-17638 has a CVSS v3 base score of 9.4 (NVD).
How do I remediate CVE-2019-17638?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2019-17638, 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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