Red Hat Enterprise Linux 7.7 update for bind

1) Reachable Assertion

EUVDB-ID: #VU52736

Risk: Medium

CVSSv3.1: 6.5 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2021-25215

CWE-ID: CWE-617 - Reachable Assertion

Exploit availability: No

Description

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

The vulnerability exists due to a reachable assertion when processing DNAME records. A remote attacker can force named to add the same RRset to the ANSWER section more than once, trigger an assertion failure and crash the service. Both authoritative and recursive servers are affected by this issue during zone transfers.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Red Hat Enterprise Linux EUS Compute Node: 7.7

Red Hat Enterprise Linux for x86_64 - Extended Update Support: 7.7

Red Hat Enterprise Linux Server for x86_64 - Update Services for SAP Solutions: 7.7

Red Hat Enterprise Linux Server for Power LE - Update Services for SAP Solutions: 7.7

Red Hat Enterprise Linux Server - TUS: 7.7

Red Hat Enterprise Linux for Power, little endian - Extended Update Support: 7.7

Red Hat Enterprise Linux for Power, big endian - Extended Update Support: 7.7

Red Hat Enterprise Linux for IBM z Systems - Extended Update Support: 7.7

Red Hat Enterprise Linux Server - AUS: 7.7

bind (Red Hat package) main: before 9.11.4-9.P2.el7_7.5

CPE2.3

• cpe:2.3:o:red_hat:red_hat_enterprise_linux_eus_compute_node:7.7:*:*:*:*:red_hat_enterprise_linux:*:
• cpe:2.3:o:red_hat:red_hat_enterprise_linux_for_x86_64_-_extended_update_support:7.7:*:*:*:*:red_hat_enterprise_linux:*:
• cpe:2.3:o:red_hat:red_hat_enterprise_linux_server_-_update_services_for_sap_solutions:7.7:*:*:*:*:*:*:
• cpe:2.3:o:red_hat:red_hat_enterprise_linux_server_for_ibm_power_le_-_update_services_for_sap_solutions:7.7:*:*:*:*:*:*:
• cpe:2.3:o:red_hat:red_hat_enterprise_linux_server_-_tus:7.7:*:*:*:*:red_hat_enterprise_linux:*:
• cpe:2.3:o:red_hat:red_hat_enterprise_linux_for_power_little_endian_-_extended_update_support:7.7:*:*:*:*:red_hat_enterprise_linux:*:
• cpe:2.3:o:red_hat:red_hat_enterprise_linux_for_power_big_endian_-_extended_update_support:7.7:*:*:*:*:red_hat_enterprise_linux:*:
• cpe:2.3:o:red_hat:red_hat_enterprise_linux_for_ibm_z_systems_-_extended_update_support:7.7:*:*:*:*:red_hat_enterprise_linux:*:
• cpe:2.3:o:red_hat:red_hat_enterprise_linux_server_-_aus:7.7:*:*:*:*:red_hat_enterprise_linux:*:

External links

http://access.redhat.com/errata/RHSA-2021:1477

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

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