Denial of service in MIT Kerberos 5

1) Access of Uninitialized Pointer

EUVDB-ID: #VU79586

Risk: Medium

CVSSv3.1: 5.7 [CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2023-36054

CWE-ID: CWE-824 - Access of Uninitialized Pointer

Exploit availability: No

Description

The vulnerability allows a remote user to perform a denial of service (DoS) attack.

The vulnerability exists due to the  _xdr_kadm5_principal_ent_rec() function in lib/kadm5/kadm_rpc_xdr.c does not validate the relationship between n_key_data and the key_data array count and frees an uninitialized pointer. A remote user can send a specially crafted request to the application and perform a denial of service (DoS) attack.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Kerberos 5: 1.0 - 1.21

External links

http://github.com/krb5/krb5/compare/krb5-1.20.1-final...krb5-1.20.2-final
http://github.com/krb5/krb5/commit/ef08b09c9459551aabbe7924fb176f1583053cdd
http://github.com/krb5/krb5/compare/krb5-1.21-final...krb5-1.21.1-final

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote authenticated user via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.