CVE-2020-9484

High

High exploit probability or critical severity with a known exploit.

CVSS base

7.0 HIGH

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

EPSS — probability of exploitation (30 days)

56.6%

99.0th percentile

CISA KEV

Not listed

Weakness / dates

CWE-502

Published 2020-05-20 · modified 2026-08-25

CVSS breakdown

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

Attack Vector	L	Local
Attack Complexity	H	High
Privileges Required	L	Low
User Interaction	N	None
Scope	U	Unchanged
Confidentiality	H	High
Integrity	H	High
Availability	H	High

Timeline

2020-05-20 — Published (NVD)
2026-08-25 — Last modified (NVD)

Description

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.

Affected

apache canonical debian fedoraproject mcafee opensuse oracle

References

Official: NVD · CVE.org