Is there a public exploit for CVE-2026-126616?

No public exploit for CVE-2026-126616 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-2026-126616?

CVE-2026-126616 scores CVSS 5.3 (v3.1), rated medium.

What does CVE-2026-126616 affect?

CVE-2026-126616 affects Progressive Robot Ltd hMailServer.

5.3 Medium

The auto-ban of Progressive Robot hMailServer 6.2.0 through 6.3.3, with a MySQL or MariaDB database, can be kept from banning an address…

CVE-2026-126616

The auto-ban of Progressive Robot hMailServer 6.2.0 through 6.3.3, with a MySQL or MariaDB database, can be kept from banning an address after repeated failed logons, which allows a remote unauthenticated attacker to go on guessing account passwords from a single address without being banned. The server makes its MySQL tables in MySQL's utf8 character set, which holds no character outside the Basic Multilingual Plane, sends its statements as UTF-8 over a utf8mb4 connection and leaves the database's default strict mode in place. From 6.2.0 it decodes the user name of a SASL PLAIN logon as UTF-8, so the name can hold such a character. When the failed logons counted from one address reach MaxInvalidLogonAttempts (3 by default), the server clears that address's count, saves an IP range named "Auto-ban: " followed by the user name of the logon that reached the limit, and drops the connection. If such a character is in the part of the user name that the range's name keeps (the name is cut to 100 characters), the database refuses the range: no range is saved, the address is not refused, and, its count having already been cleared, it is given the next full set of attempts. An attacker can…

Assessment

CVSS: 5.3 (v3.1)
Severity: Medium
Known exploited: Not listed in CISA KEV
Exploit availability: Nothing found in Exploit-DB, Metasploit, Nuclei or public PoC repositories
Published: 11 November 2026
Last updated: 11 November 2026
Affected: Progressive Robot Ltd · hMailServer
Assigner: GitLab

CVSS vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

At the source

EUVD (ENISA)

References

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