Reference page — cumulative record through Monday, October 19, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.

CVE-2020-13934

CVE-2020-13934HIGH

n/a Apache Tomcat — 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 pro…

  AV  AC  PR  UI  S  C  I  A   CVSS    EPSS   %ile   KEV
   N   L   N   N  U  N  N  H    7.5   .6412   99.2     —

AFFECTED
  Product        Versions                                                                     Fixed
  Apache Tomcat  Apache Tomcat 10.0.0-M1 to 10.0.0-M6, 9.0.0.M5 to 9.0.36, 8.5.1 to 8.5.56 –  —

TIMELINE
  Jun 8   Reserved by apache
  Jul 14  Published (CNA: apache)
  Oct 8   ENRICHED — CVE-2020-13934 (Apache Tomcat). Received CVSS 7.5 and CPE data from NVD.

CWE-401, CWE-476 · CNA: apache · CVSS v3.1 · 13 references · NVD status: Modified

Description

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.

Lifecycle

Complete event history — 3 events, chronological
Date	Event	Detail
June 8, 2020	Reserved	Reserved by apache
July 14, 2020	Published	Published (CNA: apache)
October 8, 2026	ENRICHED	ENRICHED — CVE-2020-13934 (Apache Tomcat). Received CVSS 7.5 and CPE data from NVD.

Affected

Affected products and packages — 1 row
Vendor	Product / Package	Ecosystem	Version introduced	Fixed
n/a	Apache Tomcat	—	Apache Tomcat 10.0.0-M1 to 10.0.0-M6, 9.0.0.M5 to 9.0.36, 8.5.1 to 8.5.56	—

Weaknesses

CWE-401 · CWE-476

References (13)

http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00084.html [Mailing List, Third Party Advisory]
http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00088.html [Mailing List, Third Party Advisory]
https://lists.apache.org/thread.html/r61f411cf82488d6ec213063fc15feeeb88e31b0ca9c29652ee4f962e%40%3Cannounce.tomcat.apache.org%3E [Mailing List, Release Notes, Vendor Advisory]
https://lists.apache.org/thread.html/ra072b1f786e7d139e86f1d1145572e0ff71cef38a96d9c6f5362aac8%40%3Cdev.tomcat.apache.org%3E
https://lists.debian.org/debian-lts-announce/2020/07/msg00017.html [Mailing List, Third Party Advisory]
https://security.netapp.com/advisory/ntap-20200724-0003/ [Third Party Advisory]
https://usn.ubuntu.com/4596-1/ [Third Party Advisory]
https://www.debian.org/security/2020/dsa-4727 [Third Party Advisory]
https://www.oracle.com//security-alerts/cpujul2021.html [Patch, Third Party Advisory]
https://www.oracle.com/security-alerts/cpuApr2021.html [Patch, Third Party Advisory]
https://www.oracle.com/security-alerts/cpujan2021.html [Patch, Third Party Advisory]
https://www.oracle.com/security-alerts/cpujan2022.html [Patch, Third Party Advisory]
https://www.oracle.com/security-alerts/cpuoct2020.html [Patch, Third Party Advisory]

Authoritative record: CVE-2020-13934 at cve.org

Weaknesses: CWE-401 · CWE-476

About this page

This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2020-13934 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Monday, October 19, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.