Node impersonation through unauthorized certificate renewal in Icinga

1) Improper certificate validation

EUVDB-ID: #VU109861

Risk: High

CVSSv4.0: 4.5 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:L/SI:H/SA:N/E:U/U:Amber]

CVE-ID: CVE-2025-48057

CWE-ID: CWE-295 - Improper Certificate Validation

Exploit availability: No

Description

The vulnerability allows a remote attacker to impersonate trusted nodes.

The vulnerability exists due to an error within the VerifyCertificate() function that can be tricked into issuing a valid certificate. A remote attacker can send a specially crafted certificate request and request renewal of an already existing certificate, resulting in the attacker obtaining a valid certificate that can be used to impersonate trusted nodes.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Icinga: 2.0.0 - 2.14.5

CPE2.3

• cpe:2.3:a:Icinga:icinga:*:*:*:*:*:*:*:*
• cpe:2.3:a:Icinga:icinga:2.0.1:*:*:*:*:*:*:*
• cpe:2.3:a:Icinga:icinga:2.0.2:*:*:*:*:*:*:*
• cpe:2.3:a:Icinga:icinga:2.1.0:*:*:*:*:*:*:*
• cpe:2.3:a:Icinga:icinga:2.1.1:*:*:*:*:*:*:*
• cpe:2.3:a:Icinga:icinga:2.2.0:*:*:*:*:*:*:*
• cpe:2.3:a:Icinga:icinga:2.2.1:*:*:*:*:*:*:*
• cpe:2.3:a:Icinga:icinga:2.2.2:*:*:*:*:*:*:*
• cpe:2.3:a:Icinga:icinga:2.2.3:*:*:*:*:*:*:*
• cpe:2.3:a:Icinga:icinga:2.2.4:*:*:*:*:*:*:*

External links

https://github.com/Icinga/icinga2/security/advisories/GHSA-7vcf-f5v9-3wr6

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.