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

Vulnerability from cvelistv5 – Published: 2026-10-08 20:15 – Updated: 2026-10-14 01:18
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
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-10-14 01:18 UTC
CWE
  • CWE-476 - NULL Pointer Dereference
Assigner
VulnCheck CNA under the mitre root
CNA scorecard B 84/100 over 6753 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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  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
Vulnerability timeline

Sightings and recorded dates, grouped by day · UTC

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