CVE-2026-11850 – Krb5: krb5: integer underflow in berval2tl_data() leads to heap out-of-bounds read

CVE ID :CVE-2026-11850

Published : June 11, 2026, 10:16 a.m. | 1 hour, 3 minutes ago

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.
The attack vector involves a malicious or compromised LDAP KDB backend returning a krbExtraData attribute with bv_len
Severity: 5.0 | MEDIUM

Visit the link for more details, such as CVSS details, affected products, timeline, and more…