CVE-2021-3688

Severity: medium (CVSS 4.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.6% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2022-08-26 · updated 2026-06-17
Weakness: CWE-200

Description

A flaw was found in Red Hat JBoss Core Services HTTP Server in all versions, where it does not properly normalize the path component of a request URL contains dot-dot-semicolon(s). This flaw could allow an attacker to access unauthorized information or possibly conduct further attacks. The highest threat from this vulnerability is to data confidentiality and integrity.

Affected products

JBCS httpd: before 2.4.37; 2.4.37, 2.4.37-sp1, 2.4.37-sp2, 2.4.37-sp3, 2.4.37-sp4, 2.4.37-sp5 (+4) — fixed in 2.4.37

How to fix

Upgrade to a fixed version: JBCS httpd 2.4.37. Check the vendor advisory for mitigations.

References

https://access.redhat.com/security/cve/CVE-2021-3688
https://bugzilla.redhat.com/show_bug.cgi?id=1990252
https://access.redhat.com/security/cve/CVE-2021-3688
https://bugzilla.redhat.com/show_bug.cgi?id=1990252

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