Red Hat Enterprise Linux 9 update for mysql

1) Improper input validation

EUVDB-ID: #VU103175

Risk: Medium

CVSSv4.0: 6.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2025-21521

CWE-ID: CWE-20 - Improper input validation

Exploit availability: No

Description

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

The vulnerability exists due to improper input validation within the Server: Thread Pooling component in MySQL Server. A remote non-authenticated attacker can exploit this vulnerability to perform a denial of service (DoS) attack.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Red Hat Enterprise Linux for x86_64 - Extended Update Support: 9.4

Red Hat Enterprise Linux Server - AUS: 9.4

Red Hat Enterprise Linux for IBM z Systems - Extended Update Support: 9.4

Red Hat Enterprise Linux for Power, little endian - Extended Update Support: 9.4

Red Hat Enterprise Linux for ARM 64 - Extended Update Support: 9.4

Red Hat Enterprise Linux Server for Power LE - Update Services for SAP Solutions: 9.4

mysql (Red Hat package): before 8.0.40-1.el9_4

CPE2.3

• cpe:2.3:o:red_hat:red_hat_enterprise_linux_for_x86_64_-_extended_update_support:9.4:*:*:*:*:red_hat_enterprise_linux:*:*
• cpe:2.3:o:red_hat:red_hat_enterprise_linux_server_-_aus:9.4:*:*:*:*:red_hat_enterprise_linux:*:*
• cpe:2.3:o:red_hat:red_hat_enterprise_linux_for_ibm_z_systems_-_extended_update_support:9.4:*:*:*:*:red_hat_enterprise_linux:*:*
• cpe:2.3:o:red_hat:red_hat_enterprise_linux_for_power_little_endian_-_extended_update_support:9.4:*:*:*:*:red_hat_enterprise_linux:*:*
• cpe:2.3:o:red_hat:red_hat_enterprise_linux_for_arm_64_-_extended_update_support:9.4:*:*:*:*:red_hat_enterprise_linux:*:*
• cpe:2.3:o:red_hat:red_hat_enterprise_linux_server_for_ibm_power_le_-_update_services_for_sap_solutions:9.4:*:*:*:*:*:*:*
• cpe:2.3:o:red_hat:mysql_redhat_package:*:*:*:*:*:red_hat_enterprise_linux:*:*

External links

https://access.redhat.com/errata/RHSA-2025:1756

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.