Answer in brief
CVE-2020-9484 records a High severity vulnerability in Potential remote code execution in Apache Tomcat. The current sources do not mark it as known exploited. The current feed maps org.apache.tomcat.embed:tomcat-embed-core (maven), org.apache.tomcat.embed:tomcat-embed-core (maven), org.apache.tomcat.embed:tomcat-embed-core (maven), org.apache.tomcat.embed:tomcat-embed-core (maven) and additional mapped packages. Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps org.apache.tomcat.embed:tomcat-embed-core (maven), org.apache.tomcat.embed:tomcat-embed-core (maven), org.apache.tomcat.embed:tomcat-embed-core (maven), org.apache.tomcat.embed:tomcat-embed-core (maven) and additional mapped packages. Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| org.apache.tomcat.embed:tomcat-embed-coremaven | >=10.0.0-M1,<=10.0.0-M4 | 10.0.0-M5 |
| org.apache.tomcat.embed:tomcat-embed-coremaven | >=9.0.0,<9.0.35 | 9.0.35 |
| org.apache.tomcat.embed:tomcat-embed-coremaven | >=8.0.0,<8.5.55 | 8.5.55 |
| org.apache.tomcat.embed:tomcat-embed-coremaven | >=7.0.0,<7.0.104 | 7.0.104 |
| org.apache.tomcat:tomcat-catalinamaven | >=10.0.0-M1,<=10.0.0-M4 | 10.0.0-M5 |
| org.apache.tomcat:tomcat-catalinamaven | >=9.0.0,<9.0.35 | 9.0.35 |
| org.apache.tomcat:tomcat-catalinamaven | >=8.0.0,<8.5.55 | 8.5.55 |
| org.apache.tomcat:tomcat-catalinamaven | >=7.0.0,<7.0.104 | 7.0.104 |
Published upstream
May 21, 2020
Evidence: source:ghsa:source_dates:source-dates:recordSource modified
Aug 25, 2026
Evidence: source:ghsa:source_dates:source-dates:recordFirst seen by HOL
Aug 25, 2026
When using Apache Tomcat versions 10.0.0-M1 to 10.0.0-M4, 9.0.0.M1 to 9.0.34, 8.5.0 to 8.5.54 and 7.0.0 to 7.0.103 if a) an attacker is able to control the contents and name of a file on the server; and b) the server is configured to use the PersistenceManager with a FileStore; and c) the PersistenceManager is configured with sessionAttributeValueClassNameFilter="null" (the default unless a SecurityManager is used) or a sufficiently lax filter to allow the attacker provided object to be deserialized; and d) the attacker knows the relative file path from the storage location used by FileStore to the file the attacker has control over; then, using a specifically crafted request, the attacker will be able to trigger remote code execution via deserialization of the file under their control. Note that all of conditions a) to d) must be true for the attack to succeed.
Quoted source text, attributed separately from HOL analysis.