CVE-2020-13935 Apache Tomcat
| Affected software | Apache Tomcat |
|---|---|
| Severity | 7.5 High CVSS 3.1 2 scores |
| Fixed in | 10.0.0-M7, 9.0.37, 8.5.57, 7.0.105 |
| Weakness | CWE-835 |
| Published | 14 Jul 2020 |
| Updated | 8 Oct 2026 |
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 trigger an infinite loop. Multiple requests with invalid payload lengths could lead to a denial of service.
Exploitation status
Working exploit published
A reviewed exploit catalogue lists ready-to-run exploit code for this CVE.
Exploitation status
- CISA KEV not listed
- VulnCheck KEV not listed
- CISA Vulnrichment exploitation: none
- Indexed PoC 2 indexed Published artifacts you can open, in GitHub PoC, Nuclei; first seen 2020-11-02.
- EPSS 87% chance in 30 days A model's forecast, not a report of exploitation. Higher than 99.7% of all scored CVEs.
| Index | Artifact | Stars | First seen |
|---|---|---|---|
| GitHub PoC | Exploit for WebSocket Vulnerability in Apache Tomcat | 167 | 2020-11-02 |
| Nuclei | Apache Tomcat WebSocket Frame Payload Length Validation Denial of Service |
Waratek protection
A kind of vulnerability Waratek's rules address, with exploit code published or exploitation reported. No rule exists and none is planned yet. The decision below says what we found to build a rule from.
- Protection none
- Action unverified
- Review automated Inferred
- Record active
| Decided by | The affected package being open source on Maven, so the fix can be read |
|---|---|
| Finding | This CVE affects an open-source Java library published on Maven Central (Maven packages: org.apache.tomcat:tomcat, org.apache.tomcat.embed:tomcat-embed-websocket, org.apache.tomcat:tomcat-websocket), so it is squarely in ARMR's territory and the source needed to understand the defect is public. That makes it a candidate for an ARMR patch rule. No rule exists and none is scheduled: the diff between the affected and fixed versions has not been read, and a closer look may find no hook point ARMR can act on. |
CVSS
7.5 HIGH
v3.1 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
2 metrics
CVSS
7.5 HIGH v3.1CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
2 metrics
We show the highest score from the newest CVSS version. Scores from different versions can't be compared, and the first score listed is sometimes a 0.0 placeholder.
| Version | Score | Band | Vector | Assigner | Type | |
|---|---|---|---|---|---|---|
| CVSS 3.1 | 7.5 | HIGH | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
NVD | Primary | published |
| CVSS 2.0 | 5.0 | none | AV:N/AC:L/Au:N/C:N/I:N/A:P |
NVD | Primary |
Affected software and releases
Oracle advisories
| Advisory | Type | Quarter | Products Oracle names in its risk matrix |
|---|---|---|---|
| Oracle Critical Patch Update April 2025 ↗ | CPU | 2025-Q2 | Oracle Autonomous Health Framework / Trace File Analyzer (Apache Tomcat) (23.8.0-23.11.0, 24.1.0-24.11.0, 25.1.0, 25.2.0) |
| Oracle Critical Patch Update January 2022 ↗ | CPU | 2022-Q1 | Oracle Commerce / Endeca Application Controller (Apache Tomcat) (11.3.2) |
| Oracle Critical Patch Update July 2021 ↗ | CPU | 2021-Q3 | Oracle Supply Chain / Installation Issues (Apache Tomcat) (6.2.1.0) |
| Oracle Critical Patch Update January 2021 ↗ | CPU | 2021-Q1 | Oracle Fusion Middleware / MFT Runtime Server (Apache Tomcat) (12.2.1.3.0, 12.2.1.4.0) |
| Oracle Critical Patch Update October 2020 ↗ | CPU | 2020-Q4 | Oracle Construction and Engineering / Core (Apache Tomcat) (17.1, 17.2, 17.3) Oracle Database Server / Workload Manager (Apache Tomcat) (12.2.0.1, 18c, 19c) Oracle MySQL / Monitoring: General (Apache Tomcat) (8.0.21 and prior) |
Oracle components and versions
| Family | Component | Versions, as Oracle lists them | Read as |
|---|---|---|---|
| Oracle Autonomous Health Framework | Trace File Analyzer (Apache Tomcat) | 23.8.0-23.11.0, 24.1.0-24.11.0, 25.1.0, 25.2.0 | 25.1.0 · 25.2.0 |
| Oracle Commerce | Endeca Application Controller (Apache Tomcat) | 11.3.2 | 11.3.2 |
| Oracle Construction and Engineering | Core (Apache Tomcat) | 17.1, 17.2, 17.3 | 17.1 · 17.2 · 17.3 |
| Oracle Database Server | Workload Manager (Apache Tomcat) | 12.2.0.1, 18c, 19c | 12.2.0.1 · 18 · 19 |
| Oracle Fusion Middleware | MFT Runtime Server (Apache Tomcat) | 12.2.1.3.0, 12.2.1.4.0 | 12.2.1.3.0 · 12.2.1.4.0 |
| Oracle MySQL | Monitoring: General (Apache Tomcat) | 8.0.21 and prior | |
| Oracle Supply Chain | Installation Issues (Apache Tomcat) | 6.2.1.0 | 6.2.1.0 |
Maven packages
Affected and fixed versions, from OSV.dev| Package | Introduced | Fixed | Last affected |
|---|---|---|---|
org.apache.tomcat:tomcat |
10.0.0-M1 | 10.0.0-M7 |
unbounded |
org.apache.tomcat:tomcat |
9.0.0.M1 | 9.0.37 |
unbounded |
org.apache.tomcat:tomcat |
8.5.0 | 8.5.57 |
unbounded |
org.apache.tomcat:tomcat |
7.0.27 | 7.0.105 |
unbounded |
org.apache.tomcat.embed:tomcat-embed-websocket |
7.0.27 | 7.0.105 |
unbounded |
org.apache.tomcat.embed:tomcat-embed-websocket |
8.5.0 | 8.5.57 |
unbounded |
org.apache.tomcat.embed:tomcat-embed-websocket |
9.0.0.M1 | 9.0.37 |
unbounded |
org.apache.tomcat.embed:tomcat-embed-websocket |
10.0.0-M1 | 10.0.0-M7 |
unbounded |
org.apache.tomcat:tomcat-websocket |
10.0.0-M1 | 10.0.0-M7 |
unbounded |
org.apache.tomcat:tomcat-websocket |
9.0.0.M1 | 9.0.37 |
unbounded |
org.apache.tomcat:tomcat-websocket |
8.5.0 | 8.5.57 |
unbounded |
org.apache.tomcat:tomcat-websocket |
7.0.27 | 7.0.105 |
unbounded |
Products and versions
21 products, 86 version entries| Source | Vendor | Product | Scheme | Affected versions |
|---|---|---|---|---|
| nvd | apache | tomcat | generic | ≥ 7.0.27 and ≤ 7.0.104 · ≥ 8.5.0 and ≤ 8.5.56 · 9.0.0:milestone1 · 9.0.0:milestone10 · 9.0.0:milestone11 · 9.0.0:milestone12 · 9.0.0:milestone13 · 9.0.0:milestone14 · 9.0.0:milestone15 · 9.0.0:milestone16 · 9.0.0:milestone17 · 9.0.0:milestone18 · 9.0.0:milestone19 · 9.0.0:milestone2 · 9.0.0:milestone20 · 9.0.0:milestone21 · 9.0.0:milestone22 · 9.0.0:milestone23 · 9.0.0:milestone24 · 9.0.0:milestone25 · 9.0.0:milestone26 · 9.0.0:milestone27 · 9.0.0:milestone3 · 9.0.0:milestone4 · 9.0.0:milestone5 · 9.0.0:milestone6 · 9.0.0:milestone7 · 9.0.0:milestone8 · 9.0.0:milestone9 · ≥ 9.0.1 and ≤ 9.0.36 · 10.0.0:milestone1 · 10.0.0:milestone2 · 10.0.0:milestone3 · 10.0.0:milestone4 · 10.0.0:milestone5 · 10.0.0:milestone6 |
| nvd | canonical | ubuntu linux | generic | 16.04 · 20.04 |
| nvd | debian | debian linux | generic | 9.0 · 10.0 |
| nvd | mcafee | epolicy orchestrator | generic | 5.9.0 · 5.9.1 · 5.10.0 · 5.10.0:update_1 · 5.10.0:update_2 · 5.10.0:update_3 · 5.10.0:update_4 · 5.10.0:update_5 · 5.10.0:update_6 · 5.10.0:update_7 · 5.10.0:update_8 |
| nvd | netapp | oncommand system manager | generic | ≥ 3.0.0 and ≤ 3.1.3 |
| nvd | opensuse | leap | generic | 15.1 · 15.2 |
| nvd | oracle | agile engineering data management | generic | 6.2.1.0 |
| nvd | oracle | agile product lifecycle management | generic | 9.3.3 · 9.3.5 · 9.3.6 |
| nvd | oracle | blockchain platform | generic | < 21.1.2 |
| nvd | oracle | commerce guided search | generic | 11.3.2 |
| nvd | oracle | communications cloud native core policy | generic | 1.14.0 |
| nvd | oracle | communications instant messaging server | generic | 10.0.1.5.0 |
| nvd | oracle | fmw platform | generic | 12.2.1.3.0 · 12.2.1.4.0 |
| nvd | oracle | instantis enterprisetrack | generic | 17.1 · 17.2 · 17.3 |
| nvd | oracle | managed file transfer | generic | 12.2.1.3.0 · 12.2.1.4.0 |
| nvd | oracle | mysql enterprise monitor | generic | ≤ 8.0.21 |
| nvd | oracle | siebel ui framework | generic | ≤ 20.12 |
| nvd | oracle | workload manager | generic | 12.2.0.1 · 18c · 19c |
| osv | org.apache.tomcat | tomcat | generic | ≥ 7.0.27 and < 7.0.105 · ≥ 8.5.0 and < 8.5.57 · ≥ 9.0.0 and < 9.0.37 · ≥ 10.0.0 and < 10.0.0 |
| osv | org.apache.tomcat | tomcat-websocket | generic | ≥ 7.0.27 and < 7.0.105 · ≥ 8.5.0 and < 8.5.57 · ≥ 9.0.0 and < 9.0.37 · ≥ 10.0.0 and < 10.0.0 |
| osv | org.apache.tomcat.embed | tomcat-embed-websocket | generic | ≥ 7.0.27 and < 7.0.105 · ≥ 8.5.0 and < 8.5.57 · ≥ 9.0.0 and < 9.0.37 · ≥ 10.0.0 and < 10.0.0 |
References
Timeline
Timeline
| Published | 2020-07-14 | By the CVE Program. |
|---|---|---|
| NVD record modified | 2026-10-08 | NVD's own last-modified date for this record. |