Is there a public exploit for CVE-2026-121603?

No public exploit for CVE-2026-121603 was found in Exploit-DB, Metasploit, Nuclei templates or public proof-of-concept repositories. That is an absence of evidence rather than proof that none exists.

How severe is CVE-2026-121603?

CVE-2026-121603 scores CVSS 8.5 (v4.0), rated high.

What does CVE-2026-121603 affect?

CVE-2026-121603 affects solanum-ircd solanum.

8.5 High

Solanum before commit 2ea1382 contains a buffer overflow vulnerability in mskill() that allows malicious linked servers to corrupt memory…

CVE-2026-121603

Solanum before commit 2ea1382 contains a buffer overflow vulnerability in mskill() that allows malicious linked servers to corrupt memory by sending an overlong kill reason. Attackers controlling a rogue or compromised peer server can send a reason exceeding KILLLEN that overflows a static 512-byte buffer, crashing the ircd or potentially achieving remote code execution.

Assessment

CVSS: 8.5 (v4.0)
Severity: High
Known exploited: Not listed in CISA KEV
Exploit availability: Nothing found in Exploit-DB, Metasploit, Nuclei or public PoC repositories
Published: 3 November 2026
Last updated: 3 November 2026
Affected: solanum-ircd · solanum
Assigner: VulnCheck

CVSS vectorCVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N

At the source

EUVD (ENISA)

References

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