MEDIUM
CVE-2021-33910
CWE-770Published: July 20, 2021· Updated: Jun 17, 2026
5.5
CVSS v3.1
Official Description
basic/unit-name.c in systemd prior to 246.15, 247.8, 248.5, and 249.1 has a Memory Allocation with an Excessive Size Value (involving strdupa and alloca for a pathname controlled by a local attacker) that results in an operating system crash.
Technical Analysis
CVE-2021-33910 requires local access, meaning attackers must already have a foothold on the target system.
Exploitation requires low privileges, which limits the exposure to scenarios where an attacker has already gained initial access.
A successful exploit results in availability disruption (denial of service), with a CVSS base score of 5.5.
CVSS v3.1 Vector Breakdown
Exploitability
Attack VectorLocal
Attack ComplexityLow
Privileges Req.Low
User InteractionNone
ScopeUnchanged
Impact
ConfidentialityNone
IntegrityNone
AvailabilityHigh
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Affected Vendors & Products
Debian1 product(s)
debian linux
Fedora1 product(s)
fedora
netapp2 product(s)
hci management nodesolidfire
systemd_project1 product(s)
systemd
Source: NVD CPE · 6 total CPE entries
Exploit & PoC Resources
NO KNOWN EXPLOITNo public exploit confirmed at this time
Exploit-DB
Offensive Security exploit database
GitHub PoC Search
Community PoC repositories
Rapid7 / Metasploit
Metasploit module search
PacketStorm
Security advisories & exploits
NVD Detail
Official NIST entry
MITRE CVE
CVE Program entry
External links open in a new tab. Always verify in a controlled environment before use.
Official Patches & Advisories
All References (34)
→
http://packetstormsecurity.com/files/163621/Sequoia-A-Deep-Root-In-Linuxs-Filesystem-Layer.htmlExploit · Third Party Advisory · VDB Entry
→
http://www.openwall.com/lists/oss-security/2021/08/04/2Mailing List · Patch · Third Party Advisory
→
http://www.openwall.com/lists/oss-security/2021/08/17/3Mailing List · Patch · Third Party Advisory
→
http://www.openwall.com/lists/oss-security/2021/09/07/3Mailing List · Patch · Third Party Advisory
→
https://github.com/systemd/systemd-stable/commit/4a1c5f34bd3e1daed4490e9d97918e504d19733bPatch · Third Party Advisory
→
https://github.com/systemd/systemd-stable/commit/764b74113e36ac5219a4b82a05f311b5a92136cePatch · Third Party Advisory
→
https://github.com/systemd/systemd-stable/commit/b00674347337b7531c92fdb65590ab253bb57538Patch · Third Party Advisory
→
https://github.com/systemd/systemd-stable/commit/cfd14c65374027b34dbbc4f0551456c5dc2d1f61Patch · Third Party Advisory
→
https://github.com/systemd/systemd/commit/b34a4f0e6729de292cb3b0c03c1d48f246ad896bPatch · Third Party Advisory
→
https://github.com/systemd/systemd/pull/20256/commits/441e0115646d54f080e5c3bb0ba477c892861ab9Patch · Third Party Advisory
→
https://security.gentoo.org/glsa/202107-48Third Party Advisory
→
https://security.netapp.com/advisory/ntap-20211104-0008/Third Party Advisory
Quick Facts
CVE IDCVE-2021-33910
CVSS Score5.5 / 10
SeverityMEDIUM
WeaknessCWE-770
CISA KEVNo
Affected4 vendor(s)
PublishedJul 20, 2021
Related CVEs (CWE-770)
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2021-33910 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts
Data sourced from NVD (NIST), CISA KEV, and EPSS (FIRST). Analysis generated by CTIWatch. CVE data is provided under the NVD usage policy.