7.5

CVE-2021-44758: heimdal_project heimdal NULL Pointer Dereference

Modified
AliasesALPINE-CVE-2021-44758UBUNTU-CVE-2021-44758DEBIAN-CVE-2021-44758
Published 26-12-2022Last modified 14-04-2025

Vulnerability summary

CVE-2021-44758 is a high (CVSS 7.5) NULL Pointer Dereference vulnerability in heimdal_project heimdal. EPSS estimates a 1.33% chance of exploitation in the next 30 days, higher than 71% of scored vulnerabilities.

Priority
Prioritisesevere

Severe, CVSS 7.5 (CVE.org); no exploitation reported by the 5 checked sources; EPSS 1% (FIRST, 03-11-2026)

Source freshness unavailable

How is this decided?
CVSS score
7.5/10
010
High · v3.1 (CVE.org)
EPSS score
1.33%
0%100%
Low · +0.11 pp in 30 days
KEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 6 · Related 3
DLA-3206-1DSA-5287-1MGASA-2022-0468OPENSUSE-SU-2023:0019-1OPENSUSE-SU-2023:0020-1USN-5800-1

Timeline

  1. 26-12-2022
    PublishedVulnerability first disclosed.
  2. 14-04-2025
    Last modifiedVulnerability information updated.

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.

CVSS metrics

5 scores · 5 sources · 1 version

EPSS trend

Probability

1.33%

Chance of exploitation in the next 30 days

Percentile

71%

Versus all other CVEs

30-day change

Increase +0.11 pp

From 1.22% on 04-10-2026

04-10-202603-11-2026

Known exploited

Compare KEV catalogs
CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Version check

Known conditions: network-reachable, no authentication, no user interaction (CVSS vector). Other conditions: not stated in public data.

Alpine1 product
  • heimdal< 7.7.1-r0
Debian1 product
  • heimdal< 7.8.git20221115.a6cf945+dfsg-1
Heimdal_project1 product
Ubuntu1 product
  • heimdal< 1.6~git20131207+dfsg-1ubuntu1.2+esm3 | < 1.7~git20150920+dfsg-4ubuntu1.16.04.1+esm3 | < 7.5.0+dfsg-1ubuntu0.3 | < 7.7.0+dfsg-1ubuntu1.3 | All versions (No fix recorded)

4 vendors · 4 products

References

9 links