Answer in brief
CVE-2026-107587 records a Medium severity (CVSS 5.9) vulnerability in Improper Certificate Validation in hMailServer. The current sources do not mark it as known exploited. The current feed maps Progressive Robot Ltd/hMailServer (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 5.9. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Progressive Robot Ltd/hMailServer (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Progressive Robot Ltd/hMailServergeneric | >=6.3.2 <6.3.6 | 6.3.6 |
Published upstream
Oct 8, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Oct 8, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Oct 8, 2026
Improper certificate validation in the webmail of Progressive Robot hMailServer 6.3.2 through 6.3.5 allows a remote unauthenticated attacker to have S/MIME-encrypted mail that the account later sends to another correspondent also encrypted to the attacker's key. When its recipient opened a signed message, the webmail kept the signer's certificate for encrypting replies whether or not the server found its chain trusted, under the first e-mail address the certificate listed rather than the message's From address, and beside any certificate already held for that address. Encrypted mail later sent from the webmail to that address was encrypted to every certificate held for it, so a holder of the kept certificate's key who obtains a copy of such a message can read it.
Quoted source text, attributed separately from HOL analysis.