How severe is CVE-2021-44758?

CVE-2021-44758 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2021-44758 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (65th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-44758?

CVE-2021-44758 affects Heimdal Project Heimdal. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-44758?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2021-44758 published?

CVE-2021-44758 was published on 2022-12-26 and last updated on 2026-06-17.

CVE-2021-44758

CVE-2021-44758 is a high-severity vulnerability in Heimdal Project Heimdal with a CVSS 3.x base score of 7.5. 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-476.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 1% (65th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-476
Affected product: Heimdal Project Heimdal
Published: 2022-12-26
Last modified: 2026-06-17

Description

Heimdal before 7.7.1 allows attackers to cause a NULL pointer dereference in a SPNEGO acceptor via a preferred_mech_type of GSS_C_NO_OID and a nonzero initial_response value to send_accept.

Frequently asked questions

What is CVE-2021-44758?: Heimdal before 7.7.1 allows attackers to cause a NULL pointer dereference in a SPNEGO acceptor via a preferred_mech_type of GSS_C_NO_OID and a nonzero initial_response value to send_accept.
How severe is CVE-2021-44758?: CVE-2021-44758 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2021-44758 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (65th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-44758?: CVE-2021-44758 affects Heimdal Project Heimdal. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-44758?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-44758 published?: CVE-2021-44758 was published on 2022-12-26 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:heimdal_project:heimdal:*:*:*:*:*:*:*:*

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