CVE-2026-107708 (GCVE-0-2026-107708)

Vulnerability from cvelistv5 – Published: 2026-10-08 20:15 – Updated: 2026-10-08 20:15
VLAI
Title
MIT krb5 through 1.22.2 KDC NULL Pointer Dereference via S4U2Proxy PAC
Summary
MIT krb5 through 1.22.2 contains a NULL pointer dereference vulnerability in the KDC's get_pac_princ_with_realm() that returns success while leaving the client principal NULL on malformed names. A malicious or compromised cross-realm trusted KDC can send an S4U2Proxy request with a PAC carrying a malformed client name to crash krb5kdc and deny authentication.
Severity
6.9 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
4.9 (Medium)
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H
CWE
  • CWE-476 - NULL Pointer Dereference
Assigner
VulnCheck CNA under the mitre root
CNA scorecard B 84/100 over 5277 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
MIT krb5 Affected: 0 , ≤ 1.22.2 (custom)
    cpe:2.3:a:mit:kerberos_5:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-05-19 00:00
Credits
Tristan Madani
Show details on NVD website
To clipboard 

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