CVE-2026-11850

Severity CVSS v4.0:

Pending analysis

Type:

CWE-191 Integer Underflow (Wrap or Wraparound)

Publication date:

11/06/2026

Last modified:

12/06/2026

Description

An integer underflow vulnerability was found in MIT krb5 in the berval2tl_data() function in plugins/kdb/ldap/libkdb_ldap/ldap_principal2.c. The function performs an unsigned subtraction (bv_len - 2) without a prior bounds check. When bv_len is 0 or 1, the subtraction wraps to a large value which is then truncated to uint16_t, yielding 0xFFFE (65534) or 0xFFFF (65535). The subsequent malloc succeeds and memcpy reads up to 65534 bytes from a 0-1 byte buffer, resulting in a heap out-of-bounds read.<br /> The attack vector involves a malicious or compromised LDAP KDB backend returning a krbExtraData attribute with bv_len

Impact

Vector 3.x

CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:L/I:N/A:H CVSS v3.1 Severity and Metrics:

Base Score: 5.00 MEDIUM
Vector: CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:L/I:N/A:H

Attack Vector (AV): Network
Attack Complexity (AC): High
Privileges Required (PR): High
User Interaction (UI): None
Scope (S): Unchanged
Confidentiality (C): Low
Integrity (I): None
Availability (A): High

Base Score 3.x

5.00

Severity 3.x

MEDIUM

CVE-2026-11850

Description

Impact

References to Advisories, Solutions, and Tools