#VU79586 Access of Uninitialized Pointer in Kerberos 5 - CVE-2023-36054

Vulnerability identifier: #VU79586

Vulnerability risk: Medium

CVSSv4.0: 4.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2023-36054

CWE-ID: CWE-824

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Kerberos 5
Client/Desktop applications / Software for system administration

Vendor: MIT

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

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External links
https://github.com/krb5/krb5/compare/krb5-1.20.1-final...krb5-1.20.2-final
https://github.com/krb5/krb5/commit/ef08b09c9459551aabbe7924fb176f1583053cdd
https://github.com/krb5/krb5/compare/krb5-1.21-final...krb5-1.21.1-final

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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.