CVE-2020-13934

HIGHNVD 7.57.5
EchelonGraph scoreMEDIUM confidence

This high-severity CVE scores 7.5 under NVD CVSS v3. EPSS exploit probability: 23.4%, top 4% 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
7.5
EchelonGraph verdictPatch this weekExploitation is likely or a public exploit exists.
  • 44 internet-exposed hosts are running an affected version right now
  • High exploitation likelihood — EPSS 64%
CISA-KEV: Not listedEPSS: 64%CVSS: 7.5Exploit: NoneExposed: 44

A fix is available — apply it.

An h2c direct connection to Apache Tomcat 10.0.0-M1 to 10.0.0-M6, 9.0.0.M5 to 9.0.36 and 8.5.1 to 8.5.56 did not release the HTTP/1.1 processor after the upgrade to HTTP/2. If a sufficient number of such requests were made, an OutOfMemoryException could occur leading to a denial of service.

Live · internet exposure

44 internet-exposed hosts are running an affected version of CVE-2020-13934 right now.

across 19 countries (Germany, United States, China, Singapore, France)top: tomcat
See the live KEV-Exposure radar →Found passively from public internet-scan data — aggregate, host-redacted.

EchelonGraph is the only CVE feed that fuses live vulnerability intelligence with its own live internet-exposure radar — so you see not just that a CVE is exploited, but how much of the internet is exposed to it right now.

CVSS v3
7.5
EG Score
7.5(medium)
EPSS
99.1%
KEV
Not listed

Published

July 14, 2020

Last Modified

November 21, 2024

Vendor Advisories for CVE-2020-13934(1)

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

Patch Availability(2)

Vendor / EcosystemFixed in / PatchReleasedSource
redhattomcat2021-08-11redhat
redhatjws5-tomcat-0:9.0.30-5.redhat_6.1.el8jws2020-08-04redhat

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

(2 across 1 ecosystem)
Maven(2)
PackageVulnerable rangeFixed inDependents
org.apache.tomcat:tomcat8.5.11 ... 8.5.9 (43 versions)8.5.56
org.apache.tomcat:tomcat-coyote8.5.11 ... 8.5.9 (43 versions)8.5.56

Weakness Classification(2)

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

All Vendor Advisories

(4)

Data Freshness Timeline

(refreshed 4× in last 7d / 25× 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. 2026-07-09 19:06 UTCEPSS rescore
  3. 2026-07-07 13:43 UTCEPSS rescore
  4. 2026-07-06 02:20 UTCEPSS rescore
  5. 2026-07-01 15:03 UTCOSV refresh
  6. 2026-07-01 15:03 UTCEPSS rescore
  7. 2026-07-01 15:03 UTCEPSS rescore
  8. 2026-06-28 04:54 UTCEPSS rescore
  9. 2026-06-28 04:54 UTCEPSS rescore
  10. 2026-06-27 03:06 UTCEPSS rescore
  11. 2026-06-25 13:47 UTCEPSS rescore
  12. 2026-06-25 13:47 UTCEPSS rescore
  13. 2026-06-24 14:03 UTCEPSS rescore
  14. 2026-06-24 14:03 UTCEPSS rescore
  15. 2026-06-23 21:31 UTCEPSS rescore
  16. 2026-06-23 21:31 UTCEPSS rescore
  17. 2026-06-17 17:50 UTCEPSS rescore
  18. 2026-06-17 17:50 UTCEPSS rescore
  19. 2026-06-15 17:46 UTCEPSS rescore
  20. 2026-06-14 23:15 UTCEPSS rescore
  21. 2026-06-14 23:15 UTCEPSS rescore
  22. 2026-06-13 23:43 UTCOSV refresh
  23. 2026-06-13 22:58 UTCEPSS rescore
  24. 2026-06-13 22:58 UTCEPSS rescore
  25. 2026-06-12 23:09 UTCEPSS rescore
Show 28 more
  1. 2026-06-11 13:58 UTCEPSS rescore
  2. 2026-06-10 22:16 UTCEPSS rescore
  3. 2026-06-10 22:16 UTCEPSS rescore
  4. 2026-06-10 13:20 UTCEPSS rescore
  5. 2026-06-08 14:15 UTCEPSS rescore
  6. 2026-06-08 14:15 UTCEPSS rescore
  7. 2026-06-07 15:23 UTCEPSS rescore
  8. 2026-06-07 15:23 UTCEPSS rescore
  9. 2026-06-06 13:45 UTCEPSS rescore
  10. 2026-06-06 13:45 UTCEPSS rescore
  11. 2026-06-06 13:45 UTCEPSS rescore
  12. 2026-06-05 22:45 UTCEPSS rescore
  13. 2026-06-05 22:45 UTCEPSS rescore
  14. 2026-06-05 06:08 UTCEPSS rescore
  15. 2026-06-04 13:10 UTCEPSS rescore
  16. 2026-06-04 13:10 UTCEPSS rescore
  17. 2026-06-02 20:11 UTCEPSS rescore
  18. 2026-06-02 20:11 UTCEPSS rescore
  19. 2026-06-01 13:50 UTCEPSS rescore
  20. 2026-05-31 00:15 UTCEPSS rescore
  21. 2026-05-31 00:14 UTCEPSS rescore
  22. 2026-05-29 13:42 UTCEPSS rescore
  23. 2026-05-29 13:42 UTCEPSS rescore
  24. 2026-05-28 13:43 UTCEPSS rescore
  25. 2026-05-28 13:43 UTCEPSS rescore
  26. 2026-05-27 13:39 UTCEPSS rescore
  27. 2026-05-27 01:26 UTCEG score recompute
  28. 2026-05-27 01:26 UTCVendor advisory

Frequently asked(5)

What is CVE-2020-13934?
CVE-2020-13934 is a high vulnerability published on July 14, 2020. An h2c direct connection to Apache Tomcat 10.0.0-M1 to 10.0.0-M6, 9.0.0.M5 to 9.0.36 and 8.5.1 to 8.5.56 did not release the HTTP/1.1 processor after the upgrade to HTTP/2. If a sufficient number of such requests were made, an OutOfMemoryException could occur leading to a denial of service.
When was CVE-2020-13934 disclosed?
CVE-2020-13934 was first published in the National Vulnerability Database on July 14, 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-2020-13934 actively exploited?
CVE-2020-13934 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 99.1% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2020-13934?
CVE-2020-13934 has a CVSS v3 base score of 7.5 (NVD).
How do I remediate CVE-2020-13934?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2020-13934, 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

See which npm, PyPI, Go, and Maven packages are affected by CVE-2020-13934

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