CVE-2026-114473 (GCVE-0-2026-114473)

Vulnerability from cvelistv5 – Published: 2026-10-21 15:12 – Updated: 2026-10-29 20:56
VLAI
Title
Incorrect Authorization in hMailServer
Summary
Incorrect authorization in the Sender Rewriting Scheme (SRS) of Progressive Robot hMailServer 6.2.1 through 6.3.6 allows a remote attacker to relay mail through the server to outside addresses. With SRS enabled, the server rewrites the envelope sender of mail it forwards to a signed SRS address at the forwarding domain, and passes a bounce to that address back to the original sender; but it took every message to a valid SRS address, whatever its sender, as delivery to a local recipient, so the relay rules and the SMTP authentication they require were not applied, and the message was delivered to the outside address the SRS address encodes. Anyone holding a valid SRS address of the server, such as the recipient of a forwarded message, could have the server relay mail to the address it encodes for 21 days, and an account holder whose account forwards to an outside mailbox could obtain one for any address. SRS is off by default.
Severity
5 (Medium)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:L/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-10-29 17:33 UTC
CWE
  • CWE-863 - Incorrect Authorization
Assigner
GitLab CNA under the mitre root
CNA scorecard B 75/100 over 304 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Progressive Robot Ltd hMailServer Affected: 6.2.1 , ≤ 6.3.6 (semver)
guessed Create a notification for this product.
Credits
Upstream hMailServer, whose public pull request 649 fixed the same flaw in its own SRS code; found and fixed in this fork by the hMailServer project's triage of it (Progressive Robot Ltd)
Show details on NVD website
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