CVE•Published 2020-07-14•Modified 2026-10-08•1 article on news•5 live references•NVD data

CVE-2020-13934Apache · Tomcat

Vulnerability data via NVD (ingested)

CVSS v3.1

7.5

HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS percentile

Exploit Prediction Scoring System · top 1% of all CVEs

Weaknesses (CWE)

CWE-401Missing Release of Memory after Effective Lifetime CWE-476NULL Pointer Dereference

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.

Timeline

Published 2020-07-14

Modified 2026-10-08

External references

NVD MITRE Exploit-DB trickest/cve VulnCheck

Search for exposed instances

Shodan + Censys queries derived from NVD's CPE data. The vuln tag catches assets Shodan has explicitly linked to this CVE; the product / banner fingerprints find exposed instances even when the vuln tag was never applied (which is common).

Shodan · vuln tag307 hosts

vuln:CVE-2020-13934

Hosts Shodan has explicitly fingerprinted as vulnerable.

Shodan · product

product:"Apache Tomcat"

All exposed Apache Tomcat instances — cross-reference with the CVE's affected-version range.

Shodan · banner/body mention

http.html:"Tomcat"

HTTP body or banner mentions "Tomcat" — catches deploys Shodan didn't identify as a product.

More intel sources (5)

Shodan report

vuln:CVE-2020-13934