CVE-2020-13935
The payload length in a WebSocket frame was not correctly validated in Apache Tomcat 10.0.0-M1 to 10.0.0-M6, 9.0.0.M1 to 9.0.36, 8.5.0 to 8.5.56 and 7.0.27 to 7.0.104. Invalid payload lengths could
02 Description
The payload length in a WebSocket frame was not correctly validated in Apache Tomcat 10.0.0-M1 to 10.0.0-M6, 9.0.0.M1 to 9.0.36, 8.5.0 to 8.5.56 and 7.0.27 to 7.0.104. Invalid payload lengths could
03 Exploitation and scoring
- Exploitation
- Assessed, none found. CISA's assessment recorded neither public exploit code nor evidence of exploitation when it was made.
- SSVC decision
- ExploitationnoneCISA recorded no public exploit code and no evidence of exploitation.
- AutomatableyesAn attacker can reliably automate reconnaissance through exploitation, so this scales.
- Technical ImpactpartialSuccessful exploitation gives limited control of the vulnerable component.
- EPSS probability
- 86.60% probability of exploitation activity in the next 30 days.
- EPSS percentile
- Equal to or higher than the score of 99.7% of scored records. A rank, not a probability.
- NVD base score
- 7.5 (CVSS v3.x), scored by the NVD independently of the CNA.
- NVD CVSS vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- NVD analysis status
- Modified. NVD last modified this record on 2026-10-08.
- Red Hat severity
- Important. Red Hat's rating for its own products, not a CVSS rating.
Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.
04 Metadata
- Published
- 2020-07-14 15:00Z6 YR AGO
- Last updated
- 2026-10-08 21:03Z20 DAYS AGO
- Reserved
- 2020-06-08
- Assigning CNA
- apache
- Record state
- PUBLISHED
- Severity
- Not rated by the issuing CNA
- CNA CVSS vector
- Not published by the issuing CNA
- Weaknesses
- CWE-835Loop with Unreachable Exit Condition ('Infinite Loop')Base
- Data version
- 5.2
- Document digest
- 077f25918fe33723e3e55afc311a333baebe23e50766ed5bf125985bb28e6c5d
05 Affected products
06 References
- lists.apache.orghttps://lists.apache.org/thread.html/rd48c72bd3255bda87564d4da3791517c074d94f8a701f93b85752651%40%3Cannounce.tomcat.apache.org%3E
- www.debian.orgDSA-4727https://www.debian.org/security/2020/dsa-4727
- lists.debian.org[debian-lts-announce] 20200722 [SECURITY] [DLA 2286-1] tomcat8 security updatehttps://lists.debian.org/debian-lts-announce/2020/07/msg00017.html
- lists.opensuse.orgopenSUSE-SU-2020:1102http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00084.html
- lists.opensuse.orgopenSUSE-SU-2020:1111http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00088.html
- usn.ubuntu.comUSN-4448-1https://usn.ubuntu.com/4448-1/
- www.oracle.comhttps://www.oracle.com/security-alerts/cpuoct2020.html
- security.netapp.comhttps://security.netapp.com/advisory/ntap-20200724-0003/
- kc.mcafee.comhttps://kc.mcafee.com/corporate/index?page=content&id=SB10332
- usn.ubuntu.comUSN-4596-1https://usn.ubuntu.com/4596-1/
- lists.apache.org[tomcat-users] 20201118 Re: Strange crash-on-takeoff, Tomcat 7.0.104https://lists.apache.org/thread.html/r4e5d3c09f4dd2923191e972408b40fb8b42dbff0bc7904d44b651e50%40%3Cusers.tomcat.apache.org%3E
- www.oracle.comhttps://www.oracle.com/security-alerts/cpujan2021.html
- www.oracle.comhttps://www.oracle.com/security-alerts/cpuApr2021.html
- www.oracle.comhttps://www.oracle.com//security-alerts/cpujul2021.html
- www.oracle.comhttps://www.oracle.com/security-alerts/cpuoct2021.html
- www.oracle.comhttps://www.oracle.com/security-alerts/cpujan2022.html
- www.oracle.comhttps://www.oracle.com/security-alerts/cpuapr2022.html
07 Fixed in
Arch Linux
- tomcat9 Fixed in 9.0.37-1
Source: Arch Linux Security Tracker, the Arch Linux security team. Reformatted by exploit.cc.
Debian 12
- tomcat9 Fixed in 9.0.37-1
Source: Debian Security Tracker, the Debian security team. Received through OSV.dev. Reformatted by exploit.cc.
Debian 13
- tomcat9 Fixed in 9.0.37-1
Source: Debian Security Tracker, the Debian security team. Received through OSV.dev. Reformatted by exploit.cc.
Debian 14
- tomcat9 Fixed in 9.0.37-1
Source: Debian Security Tracker, the Debian security team. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu 16.04 LTS
- tomcat8 Fixed in 8.0.32-1ubuntu1.13
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu 20.04 LTS
- tomcat9 Fixed in 9.0.31-1ubuntu0.1
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu Pro 14.04 LTS
- tomcat7 No fix yet
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu Pro 16.04 LTS
- tomcat7 No fix yet
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu Pro 18.04 LTS
- tomcat8 No fix yet
- tomcat9 No fix yet
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
A release or ecosystem missing from this list has no record here. It may be unaffected or not covered by the source. Source notices and licences.