How severe is CVE-2021-33910?

CVE-2021-33910 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2021-33910 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 9% (94th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-33910?

CVE-2021-33910 primarily affects Systemd Project Systemd. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-33910?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-33910 published?

CVE-2021-33910 was published on 2021-07-20 and last updated on 2026-06-17.

CVE-2021-33910

CVE-2021-33910 is a medium-severity vulnerability in Systemd Project Systemd with a CVSS 3.x base score of 5.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-770.

Key facts

Severity: Medium (CVSS 3.x base score 5.5)
CVSS v2: 4.9
EPSS exploit prediction: 9% (94th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-770
Affected product: Systemd Project Systemd
Published: 2021-07-20
Last modified: 2026-06-17

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.

Frequently asked questions

What is CVE-2021-33910?: 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.
How severe is CVE-2021-33910?: CVE-2021-33910 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2021-33910 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 9% (94th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-33910?: CVE-2021-33910 primarily affects Systemd Project Systemd. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-33910?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-33910 published?: CVE-2021-33910 was published on 2021-07-20 and last updated on 2026-06-17.

References

Affected products (6)

cpe:2.3:a:systemd_project:systemd:*:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*
cpe:2.3:a:netapp:hci_management_node:-:*:*:*:*:*:*:*
cpe:2.3:a:netapp:solidfire:-:*:*:*:*:*:*:*

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