CVE-2021-3997
A flaw was found in systemd. An uncontrolled recursion in systemd-tmpfiles may lead to a denial...
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.
Attack profile
How easy it is to exploit
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Exploit likelihood
What each source reports
NVD Score used
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.
- Record
CVE-2021-3997- CVSS 3.1
- 5.5 Medium
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-674
- Updated
- 2026-11-03
CVE List No score
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.
- Record
CVE-2021-3997- Weakness
- CWE-674
- Updated
- 2026-11-02
EUVDEUVD-2021-27187 No score
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.
- Record
EUVD-2021-27187- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-4p54-q58q-8mpc
A flaw was found in systemd. An uncontrolled recursion in systemd-tmpfiles may lead to a denial...
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.
- Record
GHSA-4p54-q58q-8mpc- CVSS 3.1
- 5.5 Medium
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-674
- Updated
- 2026-11-02
OSVAZL-10638
CVE-2021-3997 affecting package systemd for versions less than 250.3-21
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.
- Record
AZL-10638- CVSS 3.1
- 5.5 Medium
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
OSV
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.
- Record
CVE-2021-3997- CVSS 3.1
- 5.5 Medium
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-04
Show 10 moreShow less
OSVDEBIAN-CVE-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 created in /tmp.
- Record
DEBIAN-CVE-2021-3997- CVSS 3.1
- 5.5 Medium
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-03
OSVOESA-2022-1503
systemd security update
System and Service Manager.
Security Fix(es):
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.(CVE-2021-3997)
- Record
OESA-2022-1503- CVSS 3.1
- 5.5 Medium
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
OSVUBUNTU-CVE-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 created in /tmp.
- Record
UBUNTU-CVE-2021-3997- CVSS 3.1
- 5.5 Medium
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
OSVMGASA-2022-0016 No score
Updated systemd packages fix security vulnerability
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. (CVE-2021-3997)
- Record
MGASA-2022-0016- Updated
- 2026-11-02
OSVopenSUSE-SU-2022:0043-1 No score
Security update for systemd
This update for systemd fixes the following issues:
- CVE-2021-3997: Fixed an uncontrolled recursion in systemd's systemd-tmpfiles which could cause a minor denial of service. (bsc#1194178)
- Record
openSUSE-SU-2022:0043-1- Updated
- 2026-11-02
OSVopenSUSE-SU-2022:0539-1 No score
Security update for systemd
This update for systemd fixes the following issues:
- CVE-2021-3997: Fixed an uncontrolled recursion in systemd's systemd-tmpfiles (bsc#1194178).
The following non-security bugs were fixed:
- udev/net_id: don't generate slot based names if multiple devices might claim the same slot (bsc#1192637)
- localectl: don't omit keymaps files that are symlinks (bsc#1191826)
- Record
openSUSE-SU-2022:0539-1- Updated
- 2026-11-02
OSVopenSUSE-SU-2024:11731-1 No score
libsystemd0-249.7-3.1 on GA media
These are all security issues fixed in the libsystemd0-249.7-3.1 package on the GA media of openSUSE Tumbleweed.
- Record
openSUSE-SU-2024:11731-1- Updated
- 2026-11-02
OSVSUSE-SU-2022:0043-1 No score
Security update for systemd
This update for systemd fixes the following issues:
- CVE-2021-3997: Fixed an uncontrolled recursion in systemd's systemd-tmpfiles which could cause a minor denial of service. (bsc#1194178)
- Record
SUSE-SU-2022:0043-1- Updated
- 2026-11-02
OSVSUSE-SU-2022:0539-1 No score
Security update for systemd
This update for systemd fixes the following issues:
- CVE-2021-3997: Fixed an uncontrolled recursion in systemd's systemd-tmpfiles (bsc#1194178).
The following non-security bugs were fixed:
- udev/net_id: don't generate slot based names if multiple devices might claim the same slot (bsc#1192637)
- localectl: don't omit keymaps files that are symlinks (bsc#1191826)
- Record
SUSE-SU-2022:0539-1- Updated
- 2026-11-02
OSVUSN-5226-1 No score
systemd vulnerability
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.
- Record
USN-5226-1- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
systemdAzure Linux:2 |
before 250.3-21 | 250.3-21 |
systemdDebian:12 |
before 250.2-1 | 250.2-1 |
systemdDebian:13 |
before 250.2-1 | 250.2-1 |
systemdDebian:14 |
before 250.2-1 | 250.2-1 |
systemdMageia:8 |
before 246.16-2.mga8 | 246.16-2.mga8 |
systemdopenEuler:20.03-LTS-SP1 |
before 243-49.oe1 | 243-49.oe1 |
systemdopenEuler:20.03-LTS-SP2 |
before 243-50.oe1 | 243-50.oe1 |
systemdopenEuler:20.03-LTS-SP3 |
before 243-51.oe1 | 243-51.oe1 |
systemdSUSE:Linux Enterprise Module for Basesystem 15 SP3 |
before 246.16-7.33.1 | 246.16-7.33.1 |
systemdSUSE:Linux Enterprise Micro 5.1 |
before 246.16-7.33.1 | 246.16-7.33.1 |
Show 11 moreShow less
| Package | Affected | Fixed |
|---|---|---|
systemdSUSE:Linux Enterprise Module for Basesystem 15 SP3 |
before 246.16-150300.7.39.1 | 246.16-150300.7.39.1 |
systemdSUSE:Linux Enterprise Micro 5.1 |
before 246.16-150300.7.39.1 | 246.16-150300.7.39.1 |
systemdUbuntu:Pro:14.04:LTS |
All versions, plus listed versions 204-0ubuntu18204-0ubuntu19204-5ubuntu3204-5ubuntu5204-5ubuntu6 Show 40 moreShow less204-5ubuntu7204-5ubuntu8204-5ubuntu9204-5ubuntu10204-5ubuntu11204-5ubuntu13204-5ubuntu14204-5ubuntu15204-5ubuntu16204-5ubuntu17204-5ubuntu18204-5ubuntu19204-5ubuntu20204-5ubuntu20.2204-5ubuntu20.3204-5ubuntu20.4204-5ubuntu20.5204-5ubuntu20.6204-5ubuntu20.7204-5ubuntu20.8204-5ubuntu20.9204-5ubuntu20.10204-5ubuntu20.11204-5ubuntu20.12204-5ubuntu20.13204-5ubuntu20.14204-5ubuntu20.15204-5ubuntu20.18204-5ubuntu20.19204-5ubuntu20.20204-5ubuntu20.21204-5ubuntu20.22204-5ubuntu20.24204-5ubuntu20.25204-5ubuntu20.26204-5ubuntu20.28204-5ubuntu20.29204-5ubuntu20.31204-5ubuntu20.31+esm2204-5ubuntu20.31+esm3 |
None known |
systemdUbuntu:Pro:16.04:LTS |
All versions, plus listed versions 225-1ubuntu9227-2ubuntu1227-2ubuntu2228-1ubuntu2228-2ubuntu1 Show 45 moreShow less228-2ubuntu2228-3ubuntu1228-4ubuntu1228-4ubuntu2228-5ubuntu1228-5ubuntu2228-5ubuntu3228-6ubuntu1229-1ubuntu2229-1ubuntu4229-2ubuntu1229-3ubuntu1229-3ubuntu2229-4ubuntu1229-4ubuntu4229-4ubuntu5229-4ubuntu6229-4ubuntu7229-4ubuntu8229-4ubuntu10229-4ubuntu11229-4ubuntu12229-4ubuntu13229-4ubuntu16229-4ubuntu17229-4ubuntu19229-4ubuntu20229-4ubuntu21229-4ubuntu21.1229-4ubuntu21.2229-4ubuntu21.3229-4ubuntu21.4229-4ubuntu21.5229-4ubuntu21.6229-4ubuntu21.8229-4ubuntu21.9229-4ubuntu21.10229-4ubuntu21.15229-4ubuntu21.16229-4ubuntu21.17229-4ubuntu21.19229-4ubuntu21.21229-4ubuntu21.22229-4ubuntu21.23229-4ubuntu21.27 |
None known |
systemdUbuntu:Pro:18.04:LTS |
All versions, plus listed versions 234-2ubuntu12235-2ubuntu3235-3ubuntu2235-3ubuntu3237-3ubuntu3 Show 45 moreShow less237-3ubuntu4237-3ubuntu6237-3ubuntu7237-3ubuntu8237-3ubuntu10237-3ubuntu10.2237-3ubuntu10.3237-3ubuntu10.4237-3ubuntu10.6237-3ubuntu10.9237-3ubuntu10.11237-3ubuntu10.12237-3ubuntu10.13237-3ubuntu10.15237-3ubuntu10.17237-3ubuntu10.19237-3ubuntu10.20237-3ubuntu10.21237-3ubuntu10.22237-3ubuntu10.23237-3ubuntu10.24237-3ubuntu10.25237-3ubuntu10.26237-3ubuntu10.28237-3ubuntu10.29237-3ubuntu10.31237-3ubuntu10.33237-3ubuntu10.38237-3ubuntu10.39237-3ubuntu10.40237-3ubuntu10.41237-3ubuntu10.42237-3ubuntu10.43237-3ubuntu10.44237-3ubuntu10.45237-3ubuntu10.46237-3ubuntu10.47237-3ubuntu10.48237-3ubuntu10.49237-3ubuntu10.50237-3ubuntu10.51237-3ubuntu10.52237-3ubuntu10.53237-3ubuntu10.54237-3ubuntu10.56 |
None known |
systemdUbuntu:20.04:LTS |
before 245.4-4ubuntu3.15, plus listed versions 242-7ubuntu3243-2ubuntu1243-3ubuntu1244-3ubuntu1244.1-0ubuntu2 Show 19 moreShow less244.1-0ubuntu3244.2-1ubuntu1244.3-1ubuntu1245.2-1ubuntu1245.2-1ubuntu2245.4-2ubuntu1245.4-4ubuntu1245.4-4ubuntu3245.4-4ubuntu3.1245.4-4ubuntu3.2245.4-4ubuntu3.3245.4-4ubuntu3.4245.4-4ubuntu3.5245.4-4ubuntu3.6245.4-4ubuntu3.7245.4-4ubuntu3.10245.4-4ubuntu3.11245.4-4ubuntu3.13245.4-4ubuntu3.14 |
245.4-4ubuntu3.15 |
htmldocSUSE:Package Hub 15 SP3 |
before 1.9.12-bp153.2.6.1 | 1.9.12-bp153.2.6.1 |
htmldocopenSUSE:Leap 15.3 |
before 1.9.12-bp153.2.6.1 | 1.9.12-bp153.2.6.1 |
systemdopenSUSE:Leap 15.3 |
before 246.16-7.33.1 | 246.16-7.33.1 |
systemdopenSUSE:Leap 15.3 |
before 246.16-150300.7.39.1 | 246.16-150300.7.39.1 |
systemdopenSUSE:Tumbleweed |
before 249.7-3.1 | 249.7-3.1 |
History
| Recorded | Changed | Sources |
|---|---|---|
| facts | EUVD, NVD, OSV | |
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2021-3997 is a medium vulnerability (CVSS 5.5) in Systemd, published January 10, 2022. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 1.74%, the 77th percentile. Fixed in systemd 250.3-21.
References
bugzilla.redhat.com/show_bug.cgi?id=2024639
openwall.com/lists/oss-security/2022/01/10/2
github.com/systemd/systemd/commit/5b1cf7a9be37e20133c0208005274ce4a5b5c6a1
access.redhat.com/security/cve/CVE-2021-3997
security.gentoo.org/glsa/202305-15
cert-portal.siemens.com/productcert/html/ssa-398330.html
Show 20 moreShow less
nvd.nist.gov/vuln/detail/CVE-2021-3997
security-tracker.debian.org/tracker/CVE-2021-3997
advisories.mageia.org/MGASA-2022-0016.html
bugs.mageia.org/show_bug.cgi?id=29864
vulners.com/redhatcve/RH:CVE-2021-3997
lists.opensuse.org/archives/list/[email protected]/thread/BMN5QRPEKDGOKDHBMC6SXHPA733I43MV
ubuntu.com/security/notices/USN-5226-1
openeuler.org/en/security/safety-bulletin/detail.html?id=openEuler-SA-2022-1503
suse.com/support/update/announcement/2022/suse-su-20220043-1
bugzilla.suse.com/1178561
cve.org/CVERecord?id=CVE-2021-3997
Left out here: 11 versions. The JSON record has them.