CVE-2020-28196: 
MySQL vulnerability analysis and mitigation

MIT Kerberos 5 (aka krb5) before 1.17.2 and 1.18.x before 1.18.3 allows unbounded recursion via an ASN.1-encoded Kerberos message because the lib/krb5/asn.1/asn1_encode.c support for BER indefinite lengths lacks a recursion limit (NVD, MITRE).

The vulnerability exists in the ASN.1 decoder of libkrb5 where there is no limit on recursion depth when processing BER indefinite lengths. This implementation flaw in the lib/krb5/asn.1/asn1_encode.c file could allow an attacker to cause unbounded recursion. The vulnerability has been assigned a CVSS v3.1 Base Score of 7.5 (HIGH) with vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H (NVD).

A successful exploitation of this vulnerability could allow an unauthenticated attacker to cause a denial of service (DoS) condition by causing the process to crash through stack overflow. The vulnerability affects any client or server that processes ASN.1-encoded Kerberos messages (Gentoo, Debian).

The vulnerability is remotely exploitable without requiring authentication. An attacker can trigger the vulnerability by sending specially crafted ASN.1-encoded Kerberos messages of sufficient length to a target system (NetApp).

The vulnerability has been fixed in MIT Kerberos 5 versions 1.17.2 and 1.18.3. The fix implements a recursion limit for ASN.1 indefinite lengths processing. Organizations should upgrade to these patched versions or apply vendor-specific patches. Multiple vendors have released security updates including Debian, Fedora, and Gentoo (Debian, Fedora, Gentoo).