IBM AIX update for ISC BIND

1) Reliance on Reverse DNS Resolution for a Security-Critical Action

EUVDB-ID: #VU61422

Risk: Medium

CVSSv4.0: 2.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:N/VI:N/VA:N/SC:N/SI:H/SA:N/E:U/U:Green]

CVE-ID: CVE-2021-25220

CWE-ID: CWE-350 - Reliance on Reverse DNS Resolution for a Security-Critical Action

Exploit availability: No

Description

The vulnerability allows a remote attacker to poison DNS cache.

The vulnerability exists due to an error in DNS forwarder implementation. When using forwarders, bogus NS records supplied by, or via, those forwarders may be cached and used by named if it needs to recurse for any reason, causing it to obtain and pass on potentially incorrect answers. The cache could become poisoned with incorrect records leading to queries being made to the wrong servers, which might also result in false information being returned to clients.

Mitigation

Install update from vendor's website.

Vulnerable software versions

IBM AIX: 7.1 - 7.3.0.1

CPE2.3

• cpe:2.3:o:ibm_corporation:ibm_aix:7.1:*:*:*:*:*:*:*
• cpe:2.3:o:ibm_corporation:ibm_aix:7.1.1:*:*:*:*:*:*:*
• cpe:2.3:o:ibm_corporation:ibm_aix:7.1.2:*:*:*:*:*:*:*

External links

https://aix.software.ibm.com/aix/efixes/security/bind_advisory21.asc

Q & A

Can this vulnerability be exploited remotely?

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

Is there known malware, which exploits this vulnerability?

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