CVE-2021-3531

Severity: medium (CVSS 5.3 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 2.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-05-18 · updated 2026-06-17
Weakness: CWE-20

Description

A flaw was found in the Red Hat Ceph Storage RGW in versions before 14.2.21. When processing a GET Request for a swift URL that ends with two slashes it can cause the rgw to crash, resulting in a denial of service. The greatest threat to the system is of availability.

Affected products

Fedoraproject Fedora: 32, 33, 34
ceph: before 14.2.21 — fixed in 14.2.21
Red Hat Ceph Storage: 4.0

How to fix

Upgrade to a fixed version: ceph 14.2.21. Check the vendor advisory for mitigations.

References

http://www.openwall.com/lists/oss-security/2021/05/14/5
http://www.openwall.com/lists/oss-security/2021/05/17/7
https://bugzilla.redhat.com/show_bug.cgi?id=1955326
https://lists.debian.org/debian-lts-announce/2023/10/msg00034.html
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/FX5ZHI5L7FOHXOSEV3TYBAL66DMLJ7V5/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/LPCJN2YDZCBMF4FOJXSTAADKFGEQEO7O/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZRUNDH2TJRZRWL3DCH2PQ6KROWTPQ7AJ/
http://www.openwall.com/lists/oss-security/2021/05/14/5
http://www.openwall.com/lists/oss-security/2021/05/17/7
https://bugzilla.redhat.com/show_bug.cgi?id=1955326
https://lists.debian.org/debian-lts-announce/2023/10/msg00034.html
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/FX5ZHI5L7FOHXOSEV3TYBAL66DMLJ7V5/

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