Is there a public exploit for CVE-2026-126618?

No public exploit for CVE-2026-126618 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-2026-126618?

CVE-2026-126618 scores CVSS 5.3 (v3.1), rated medium.

What does CVE-2026-126618 affect?

CVE-2026-126618 affects Progressive Robot Ltd hMailServer.

5.3 Medium

The auto-ban of Progressive Robot hMailServer 6.0.0-B1 through 6.3.7 can be kept from banning an address after repeated failed logons,…

CVE-2026-126618

The auto-ban of Progressive Robot hMailServer 6.0.0-B1 through 6.3.7 can be kept from banning an address after repeated failed logons, which allows a remote unauthenticated attacker who can connect from two or more addresses to go on guessing account passwords - over SMTP AUTH, IMAP and POP3, and over ManageSieve, CalDAV/CardDAV and the REST API where those are turned on (off by default) - without being banned. When the failed logons counted from one address reach MaxInvalidLogonAttempts (3 by default), the server clears that address's count, saves an IP range that refuses the address for AutoBanMinutes (60 by default) and drops the connection. The range is named "Auto-ban: " followed by the user name of the logon that reached the limit, and no two ranges may have the same name. The server chooses the name by checking candidates as written - the name, then the name with a number, a random suffix or a GUID added - and only then cuts it to the 100 characters the database column holds, so that with a user name of 90 characters or more every candidate is the same once cut. While one range named after such a user name stands, every later ban named after a user name with the same first…

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

Community proofs of concept

No community proof of concept yet. If you have one for a published vulnerability and the right to share it, add it below — it will appear here once reviewed.

Submit a proof of concept

Only for publicly disclosed vulnerabilities, and only material from testing you were authorised to perform. This platform does not buy, sell, or broker exploits — see earning from vulnerability research for legitimate bounty programs. Submissions are reviewed before they appear. Text only; do not include live credentials, personal data, or anything targeting systems you are not permitted to test.

Title *

Proof of concept *

Write-up (optional)

Affected versions (optional)

Name or handle (optional)

References (optional, one URL per line)

Licence for your contribution *

Private contact (optional, never shown)

Before you submit * This vulnerability is already publicly disclosed (it has a published CVE). This material comes only from testing I was authorised to perform. I have the legal right to publish this content and am not breaching any agreement by doing so. It contains no live credentials, personal data, or anything targeting systems I am not authorised to test. I understand it will be reviewed before it appears publicly and may be rejected. I agree to the submission terms.

What is 4 + 6? *

Query this programmatically

Agents can read this through the MCP endpoint, or over HTTP:

curl https://cve.zerocrew.in/api/cve/CVE-2026-126618