Progressive Robot hMailServer 6.3.4 through 6.3.7, with a MySQL or MariaDB database and TlsMode=verify-full, does not
Source GCVE Database
Not known to be exploited · CVSS 7.4 High.
Data as of 11 Nov 2026, 10:05 UTC
Thin evidence
One scorer or none| CNA (GitLab) | CVSS 3.1 | 7.4 |
|---|
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:NExploitation evidence
Disclosed: evidence found.
CVE published 11 Nov 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 10 Nov 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Progressive Robot LtdhMailServer | Affected
| Fixed in– |
GitHubhmailserver/hmailserverpkg:github/hmailserver/hmailserverOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Users should verify their hMailServer configuration and avoid using TlsMode=verify-full with CA filenames containing non-ASCII characters on Linux or characters above U+00FF on Windows. Consider reverting to the default TlsMode=prefer if appropriate. Additionally, updating MariaDB Connector/C to version 3.4.11 or later, where the related certificate validation issues are fixed, is recommended. Monitor vendor advisories for official patches or updates addressing this vulnerability.
Description
Progressive Robot hMailServer versions 6.3.4 through 6.3.7, when configured with a MySQL or MariaDB database and TlsMode=verify-full, improperly handle the CA file if its filename contains non-ASCII characters on Linux or characters above U+00FF on Windows. This causes the database client not to use the specified CA file for TLS verification, allowing an attacker who can intercept the database connection to read and modify traffic by presenting a certificate that bypasses proper validation. The vulnerability arises from the server converting the CA filename to an empty string under certain locale settings, resulting in no CA file being set without error, while certificate verification remains enabled. This issue is compounded by flaws in MariaDB Connector/C versions 3.4.2 to 3.4.10, which can accept unauthorized certificates under these conditions. The default hMailServer configuration is not affected as TlsMode defaults to prefer, which does not enforce certificate checks.