CVE-2021-23240

Name: CVE-2021-23240
Creator: NVD / NIST
Published: 2021-01-12T09:15:14.107+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 7.8/10EPSS 1.07%

Last modified Jun 17, 2026

CVE-2021-23240 is a high-severity vulnerability rated 7.8/10 on the CVSS scale. selinux_edit_copy_tfiles in sudoedit in Sudo before 1.9.5 allows a local unprivileged user to gain file ownership and escalate privileges by replacing a temporary file with a symlink to an arbitrary file target. This affects SELinux RBAC support in permissive mode. EPSS estimates a 1.07% chance of exploitation in the next 30 days.

Description

selinux_edit_copy_tfiles in sudoedit in Sudo before 1.9.5 allows a local unprivileged user to gain file ownership and escalate privileges by replacing a temporary file with a symlink to an arbitrary file target. This affects SELinux RBAC support in permissive mode. Machines without SELinux are not vulnerable.

Metrics

CVSS 3.1

7.8/10

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

EPSS Probability

1.07%

60.5th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-59

Affected Software

Vendor	Product	Versions
Sudo Project	Sudo	< 1.8.32
Sudo Project	Sudo	>= 1.9.0, < 1.9.5
Netapp	Hci Management Node	All versions
Netapp	Solidfire	All versions
Fedoraproject	Fedora	32
Fedoraproject	Fedora	33

References

https://bugzilla.suse.com/show_bug.cgi?id=CVE-2021-23240Exploit, Issue Tracking, Patch, Third Party Advisory
https://lists.apache.org/thread.html/r58af02e294bd07f487e2c64ffc0a29b837db5600e33b6e698b9d696b%40%3Cissues.bookkeeper.apache.org%3E
https://lists.apache.org/thread.html/rf4c02775860db415b4955778a131c2795223f61cb8c6a450893651e4%40%3Cissues.bookkeeper.apache.org%3E
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/EE42Y35SMJOLONAIBNYNFC7J44UUZ2Y6/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/GMY4VSSBIND7VAYSN6T7XIWJRWG4GBB3/
https://security.gentoo.org/glsa/202101-33Third Party Advisory
https://security.netapp.com/advisory/ntap-20210129-0010/Third Party Advisory
https://www.sudo.ws/stable.html#1.9.5Release Notes, Vendor Advisory
https://bugzilla.suse.com/show_bug.cgi?id=CVE-2021-23240Exploit, Issue Tracking, Patch, Third Party Advisory
https://lists.apache.org/thread.html/r58af02e294bd07f487e2c64ffc0a29b837db5600e33b6e698b9d696b%40%3Cissues.bookkeeper.apache.org%3E
https://lists.apache.org/thread.html/rf4c02775860db415b4955778a131c2795223f61cb8c6a450893651e4%40%3Cissues.bookkeeper.apache.org%3E
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/EE42Y35SMJOLONAIBNYNFC7J44UUZ2Y6/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/GMY4VSSBIND7VAYSN6T7XIWJRWG4GBB3/
https://security.gentoo.org/glsa/202101-33Third Party Advisory
https://security.netapp.com/advisory/ntap-20210129-0010/Third Party Advisory
https://www.sudo.ws/stable.html#1.9.5Release Notes, Vendor Advisory

Timeline

Published: Jan 12, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-23240?

How severe is CVE-2021-23240?

CVE-2021-23240 has a CVSS score of 7.8/10 (HIGH severity). The EPSS model estimates a 1.07% probability of exploitation in the next 30 days.

How do I fix CVE-2021-23240?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-23240?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST