CVE-2026-107708CWE-476

CVE-2026-107708

Medium · published October 9, 2026

CVSS v3.1
4.9
EPSS
1%
Percentile
43.4
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
4.9 · MEDIUM
Vector
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H
CVSS v4.0
6.9 · 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
EPSS
0.00521 · 43.4th percentile
Weakness
CWE-476 · NULL Pointer Dereference
Published
2026-10-09T01:17Z
References (6)
https://github.com/krb5/krb5 · [email protected]https://github.com/krb5/krb5/blob/krb5-1.22.2-final/src/kdc/kdc_util.c#L639-L676 · [email protected]https://github.com/krb5/krb5/commit/a88a18cafa1040a0c4f9c8d08288fc98831ec86d · [email protected]https://github.com/krb5/krb5/commit/f6e2c397ceda6467ebbaab8ed66d4895c9f1d6a7 · [email protected]https://github.com/krb5/krb5/pull/1510 · [email protected]https://www.vulncheck.com/advisories/mit-krb5-through-1.22.2-kdc-null-pointer-dereference-via-s4u2proxy-pac · [email protected]
EPSS history
Timeline
  • 10 OCT 03:27Z
    EPSS moved — → 1%
    epss
  • 08 OCT 20:15Z
    MIT krb5 through 1.22.2 KDC NULL Pointer Dereference via S4U2Proxy PAC
    cvelistv5
  • 08 OCT 20:15Z
    MIT krb5 through 1.22.2 KDC NULL Pointer Dereference via S4U2Proxy PAC
    cvelistv5