CVE-2022-42898 — Integer Overflow or Wraparound in Heimdal Project Heimdal
PAC parsing in MIT Kerberos 5 (aka krb5) before 1.19.4 and 1.20.x before 1.20.1 has integer overflows that may lead to remote code execution (in KDC, kadmind, or a GSS or Kerberos application server) on 32-bit platforms (which have a resultant heap-based buffer overflow), and cause a denial of service on other platforms. This occurs in krb5_pac_parse in lib/krb5/krb/pac.c. Heimdal before 7.7.1 has "a similar bug."
Who exploits it and how urgent it is
A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.
How the score was calculated
- EPSS 6.5% (30-day exploitation probability)+14
- Technical severity (high)+6
The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.
CISA SSVC assessment CISA
Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.
Remediation
Fixes and mitigations documented by the sources — linked to the original advisory.
- Documented patch — bugzilla.samba.org (NIST National Vulnerability Database)
- Documented patch — github.com (NIST National Vulnerability Database)
First 24 hours
Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.
- Identify exposed assets running the affected vendor/product/version combinations (Heimdal Project Heimdal, Mit Kerberos 5, Samba Samba).
- Apply the fixed version or the patch documented under Remediation.
- EPSS ahead of 94% of scored CVEs: prioritize it in the patch queue.
- Search available logs for exploit probes matching the vulnerability class (memory corruption), errors and authentication anomalies.
Affected scope
Vendor, product and versions as the sources word them.
| Vendor | Product | Versions | Status | Source |
|---|---|---|---|---|
| Heimdal Project | Heimdal | < 7.7.1 | Vulnerable | NIST National Vulnerability Database |
| Mit | Kerberos 5 | ≥ 1.8 and < 1.19.4version 1.20version 1.20-beta1 | Vulnerable | NIST National Vulnerability Database |
| Samba | Samba | < 4.15.12≥ 4.16.0 and < 4.16.7≥ 4.17.0 and < 4.17.3 | Vulnerable | NIST National Vulnerability Database |
Attack characteristics
The CVSS vector, decoded. It describes the attack, not your exposure to it.
Every base score collected
Sources score independently and may disagree; each row says who scored it and under which version.
| Score | Version | Severity | Expl. | Impact | Scored by |
|---|---|---|---|---|---|
| 8.8 | CVSS 3.1 | High | 2.8 | 5.9 | nvd@nist.gov via NIST National Vulnerability Database |
| 8.8 | CVSS 3.1 | High | 2.8 | 5.9 | 134c704f-9b21-4f2e-91b3-4a467353bcc0 via NIST National Vulnerability Database |
| 8.8 | CVSS 3.1 | High | — | — | CISA-ADP via CVE Program (cve.org) e CISA ADP |
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H (score shown at the top: nvd@nist.gov) Weakness MITRE
Weakness class according to MITRE’s CWE catalog.
Detection
Read off the CVSS vector and the weakness class. Starting points, not tested rules.
- Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).
- Correlate service crashes/restarts with inbound traffic; repeated crashes may indicate attempts.
Timeline
What happened to this CVE, newest first.
- 2026
- SSVC assessment updated
- Record published
- Fix documented
- Affected products added · mit/kerberos 5, heimdal project/heimdal, samba/samba
- CVSS changed · 8.8
- Source status changed · → Modified
- Record created in this database
- 2022
- CVE published
Source activity
Repeated readings are counted rather than listed.
- 1× References added · Oct 14, 2026 – Oct 14, 2026
- 1× Official description updated · Oct 14, 2026 – Oct 14, 2026
References
12 on the record
- web.mit.edu/kerberos/krb5-1.19/
- web.mit.edu/kerberos/krb5-1.20/README-1.20.1.txt
- web.mit.edu/kerberos/advisories/
- github.com/krb5/krb5/commit/ea92d2f0fcceb54a70910fa32e9a0d7a5afc3583
- bugzilla.samba.org/show_bug.cgi
- security.netapp.com/advisory/ntap-20230223-0001/
- github.com/heimdal/heimdal/security/advisories/GHSA-64mq-fvfj-5x3c
- cert-portal.siemens.com/productcert/html/ssa-398330.html
- security.netapp.com/advisory/ntap-20230216-0008/
- security.gentoo.org/glsa/202309-06
- www.samba.org/samba/security/CVE-2022-42898.html
- security.gentoo.org/glsa/202310-06
Elsewhere on this site
Related CVEs (same products)
- Critical CVE-2026-4408 Samba: remote code execution in samr May 28, 2026
- Medium CVE-2026-1933 Samba: missing access check on reparse point operations May 27, 2026
- Medium CVE-2026-2340 Samba: vfs_worm does not block directory modification May 27, 2026
- Medium CVE-2026-3012 Samba: group policy certificate enrollment uses http:// without validation May 27, 2026
- Critical CVE-2026-4480 Samba: samba: remote code execution in printing subsystem via unescaped job description May 26, 2026
- High CVE-2026-40356 Integer Underflow in Mit Kerberos 5 Apr 28, 2026
Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.
Answered from this record
Text assembled only from the fields above — no additional claims.
What should defenders know first?
CVE-2022-42898 is "Integer Overflow or Wraparound in Heimdal Project Heimdal", rated High. It affects Heimdal (Heimdal Project); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 8.8 describes technical severity. EPSS 6.47% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.
Comments
Moderated technical discussion. Read the community guidelines.
No comments yet.
Sign in or create an account to comment and suggest corrections.