CVE-2021-3997
published 2022-08-23CVE-2021-3997: A flaw was found in systemd. An uncontrolled recursion in systemd-tmpfiles may lead to a denial of service at boot time when too many nested directories are…
PriorityP422medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
1.56%
72.5th percentile
A flaw was found in systemd. An uncontrolled recursion in systemd-tmpfiles may lead to a denial of service at boot time when too many nested directories are created in /tmp.
Affected
14 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | systemd | < systemd 250.2-1 (bookworm) | systemd 250.2-1 (bookworm) |
| fedoraproject | fedora | — | — |
| fedoraproject | fedora | — | — |
| msrc | cbl2_systemd_250.3-21_on_cbl_mariner_2.0 | — | — |
| msrc | cm1_systemd_239-42_on_cbl_mariner_1.0 | — | — |
| redhat | enterprise_linux | — | — |
| redhat | enterprise_linux | — | — |
| redhat | enterprise_linux | — | — |
| systemd_project | systemd | — | — |
| systemd_project | systemd | >= 0 < 247.3-7 | 247.3-7 |
| systemd_project | systemd | >= 0 < 250.2-1 | 250.2-1 |
| systemd_project | systemd | >= 0 < 250.2-1 | 250.2-1 |
| systemd_project | systemd | >= 0 < 250.2-1 | 250.2-1 |
| systemd_project | systemd | >= 240 < 250.2 | 250.2 |
CVSS provenance
nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
osv5.5MEDIUM
vendor_debian5.5MEDIUM
vendor_msrc5.5MEDIUM
vendor_redhat5.5MEDIUM
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GHSA
GHSA-4p54-q58q-8mpc: A flaw was found in systemd
ghsa_unreviewed·2022-08-24
CVE-2021-3997 [MEDIUM] CWE-674 GHSA-4p54-q58q-8mpc: A flaw was found in systemd
A flaw was found in systemd. An uncontrolled recursion in systemd-tmpfiles may lead to a denial of service at boot time when too many nested directories are created in /tmp.
OSV
CVE-2021-3997: A flaw was found in systemd
osv·2022-08-23·CVSS 5.5
CVE-2021-3997 [MEDIUM] CVE-2021-3997: A flaw was found in systemd
A flaw was found in systemd. An uncontrolled recursion in systemd-tmpfiles may lead to a denial of service at boot time when too many nested directories are created in /tmp.
CISA ICS
Siemens SIMATIC S7-1500 CPU 1518(F)-4 PN/DP MFP V3.1
cisa_ics·2023-12-14
Siemens SIMATIC S7-1500 CPU 1518(F)-4 PN/DP MFP V3.1
ICS Advisory
##
Siemens SIMATIC S7-1500 CPU 1518(F)-4 PN/DP MFP V3.1
Release DateDecember 14, 2023
Alert CodeICSA-23-348-10
As of January 10, 2023, CISA will no longer be updating ICS security advisories for Siemens product vulnerabilities beyond the initial advisory. For the most up-to-date information on vulnerabilities in this advisory, please see Siemens' ProductCERT Security Advisories (CERT Services | Services | Siemens Global).
View CSAF
## 1. EXECUTIVE SUMMARY
- CVSS v3 9.8
- ATTENTION: Exploitable remotely/low attack complexity
- Vendor: Siemens
- Equipment: SIMATIC S7-1500 CPU 1518(F)-4 PN/DP MFP V3.1
- Vulnerabilities: Improper Restriction of XML External Entity Reference, Time-of-check Time-of-use (TOCTOU) Race Condition, Command Injection, Miss
Microsoft
A flaw was found in systemd. An uncontrolled recursion in systemd-tmpfiles may lead to a denial of service at boot time when too many nested directories are created in /tmp.
vendor_msrc·2022-08-09·CVSS 5.5
CVE-2021-3997 [MEDIUM] CWE-674 A flaw was found in systemd. An uncontrolled recursion in systemd-tmpfiles may lead to a denial of service at boot time when too many nested directories are created in /tmp.
A flaw was found in systemd. An uncontrolled recursion in systemd-tmpfiles may lead to a denial of service at boot time when too many nested directories are created in /tmp.
FAQ: Is Azure Linux the only Microsoft product that includes this open-source library and is therefore potentially affected by this vulnerability?
One of the main benefits to our customers who choose to use the Azure Linux distro is the commitment to keep it up to date with the most recent and most secure versions of the open source libraries with which the distro is composed. Microsoft is committed to transparency in this work which is why we began publishing CSAF/VEX in October 2025. See this blog post for more information. If impact to additional products is identified, we will update the CVE to reflect this.
Mari
Ubuntu
systemd vulnerability
vendor_ubuntu·2022-01-13
CVE-2021-3997 systemd vulnerability
Title: systemd vulnerability
Summary: systemd-tmpfiles could be made to crash or have other unspecified impacts.
It was discovered that systemd-tmpfiles employed uncontrolled recursion
when removing deeply nested directory hierarchies. A local attacker could
exploit this to cause systemd-tmpfiles to crash or have other unspecified
impacts.
Instructions: In general, a standard system update will make all the necessary changes.
Red Hat
systemd: Uncontrolled recursion in systemd-tmpfiles when removing files
vendor_redhat·2022-01-10·CVSS 5.5
CVE-2021-3997 [MEDIUM] CWE-674 systemd: Uncontrolled recursion in systemd-tmpfiles when removing files
systemd: Uncontrolled recursion in systemd-tmpfiles when removing files
A flaw was found in systemd. An uncontrolled recursion in systemd-tmpfiles may lead to a denial of service at boot time when too many nested directories are created in /tmp.
A flaw was found in systemd. An uncontrolled recursion in systemd-tmpfiles may lead to a denial of service at boot time when too many nested directories are created in /tmp.
Statement: Red Hat Enterprise Linux 8 has a default 1024 nofile limit, thus preventing `systemd-tmpfiles` from exhausting its stack and crashing. For this reason, this flaw has been rated as having a security impact of Low on Red Hat Enterprise Linux 8. For more information on default ulimit values, please see https://access.redhat.com/solutions/4482841.
The systemd version
Debian
CVE-2021-3997: systemd - A flaw was found in systemd. An uncontrolled recursion in systemd-tmpfiles may l...
vendor_debian·2021·CVSS 5.5
CVE-2021-3997 [MEDIUM] CVE-2021-3997: systemd - A flaw was found in systemd. An uncontrolled recursion in systemd-tmpfiles may l...
A flaw was found in systemd. An uncontrolled recursion in systemd-tmpfiles may lead to a denial of service at boot time when too many nested directories are created in /tmp.
Scope: local
bookworm: resolved (fixed in 250.2-1)
bullseye: resolved (fixed in 247.3-7)
forky: resolved (fixed in 250.2-1)
sid: resolved (fixed in 250.2-1)
trixie: resolved (fixed in 250.2-1)
No detection rules found.
No public exploits indexed.
Qualys
Oh Snap! More Lemmings: Local Privilege Escalation Vulnerability Discovered in snap-confine (CVE-2021-44731)
blogs_qualys·2022-02-17·CVSS 7.8
[HIGH] Oh Snap! More Lemmings: Local Privilege Escalation Vulnerability Discovered in snap-confine (CVE-2021-44731)
## Table of Contents
About snap-confine
Potential Impact of Oh Snap! More Lemmings Vulnerability
Vulnerability Disclosure Timeline
Proof of Concept Video of Oh Snap! More Lemmings Exploit
Vulnerability Summary
Technical Details of Oh Snap! More Lemmings Vulnerability
Solution: How to Patch the Oh Snap! More Lemmings Vulnerability
Discover Vulnerable Linux Servers Using Qualys VMDR
Detect Impacted Assets with Threat Protection
Track Vulnerability with VMDR Dashboard
Vendor References
Frequently Asked Questions (FAQs)
The Qualys Research Team has discovered multiple vulnerabilities in the snap-confine function on Linux operating systems, the most important of which can be exploited to escalate privilege to gain root privileges. Qualys recommends security teams apply patches for
Bugzilla
CVE-2021-3997 systemd: Uncontrolled recursion in systemd-tmpfiles when removing files
bugzilla·2021-11-18·CVSS 5.5
CVE-2021-3997 [MEDIUM] CVE-2021-3997 systemd: Uncontrolled recursion in systemd-tmpfiles when removing files
CVE-2021-3997 systemd: Uncontrolled recursion in systemd-tmpfiles when removing files
A flaw was found in systemd. An uncontrolled recursion in systemd-tmpfiles may lead to denial of service at boot time.
Discussion:
Upstream commit:
https://github.com/systemd/systemd/commit/5b1cf7a9be37e20133c0208005274ce4a5b5c6a1
---
oss-security announcement by Qualys: https://www.openwall.com/lists/oss-security/2022/01/10/2.
---
Created systemd tracking bugs for this issue:
Affects: fedora-all [bug 2039383]
https://access.redhat.com/security/cve/CVE-2021-3997https://bugzilla.redhat.com/show_bug.cgi?id=2024639https://github.com/systemd/systemd/commit/5b1cf7a9be37e20133c0208005274ce4a5b5c6a1https://security.gentoo.org/glsa/202305-15https://www.openwall.com/lists/oss-security/2022/01/10/2https://access.redhat.com/security/cve/CVE-2021-3997https://bugzilla.redhat.com/show_bug.cgi?id=2024639https://github.com/systemd/systemd/commit/5b1cf7a9be37e20133c0208005274ce4a5b5c6a1https://security.gentoo.org/glsa/202305-15https://www.openwall.com/lists/oss-security/2022/01/10/2
2022-08-23
Published