CVE WatchOct 21, 2026

CVE-2026-114474

Use of a less trusted source for the envelope sender in the external-account download of Progressive Robot hMailServer 6.0.0 through 6.3.6 a

CVSS

5.9

Medium

EPSS

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KEV

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Exploit Today

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0-100

Published: Oct 21, 2026 · Last modified: Oct 21, 2026 · CWE-348

EPSS · 30d

Not enough EPSS history yet.

Technical description

Use of a less trusted source for the envelope sender in the external-account download of Progressive Robot hMailServer 6.0.0 through 6.3.6 allows a remote unauthenticated attacker to have mail they write in the name of a domain the server hosts sent on by the server with an envelope sender at that domain, so that it passes the domain's SPF and DMARC at other receivers. A message the server downloads from an external POP3 or IMAP account has no SMTP envelope of its own, and the server took the address in its From header as its envelope sender, whatever that address was. A forward or redirect of the downloaded message to an outside address then left with that address as its envelope sender, which the Sender Rewriting Scheme leaves alone for a hosted domain, so that the receiver's SPF check passed for the forged domain, aligned even under strict alignment, with no non-default setting, host name record or DMARC policy needed. An attacker needs to know a mailbox elsewhere that an account here collects and forwards to an outside address; an account holder who adds an external account of their own can collect from a server of their own, which matters where SmtpAuthenticatedSenderCheck holds signed-in senders to their own addresses.

Official references

Related CVEs

CVECVSSEPSSKEVRExploitTitleMod.

CVE-2026-1123784.3 MED

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———GitLab has remediated an issue in GitLab EE affecting all versions from 17.8 before 19.3.6, 19.4 before 19.4.3, and 19.5 before 19.5.1 that under certain conditions could have allowed an authenticated user to access paid AI features without a valid subscription due to insufficient server-side validation in billing eligibility checks.16h CVE-2026-1144374.8 MED

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———In the Golang Chi web framework, the ClientIPFromXFF middleware skips any X-Forwarded-For entry in a configured trusted CIDR but never verifies that the direct TCP peer in http.Request.RemoteAddr belongs to that CIDR. A client that can reach the Go server directly can therefore append a trusted-looking proxy address and choose the client IP returned by middleware.GetClientIP. This issue affects chi before 5.4.0.23h CVE-2026-1075677.5 HIG

5.5%

——2Use of a less trusted source in the DKIM signing of Progressive Robot hMailServer 6.0.0 through 6.3.6 allows a remote unauthenticated attacker to have mail they write signed with the DKIM key of a domain the server hosts, so that it passes DKIM and DMARC for that domain at other receivers. With DKIM signing enabled for a hosted domain, the server signed every message on its first delivery pass as the domain named in its From header, before local delivery, whatever the message's origin and without checking that its sender had authenticated. A sender anywhere could therefore send the server, as ordinary inbound mail, a message whose From is any address at such a domain, and the server signed it with that domain's key. Every copy the server then sent on to an address outside carried a valid signature aligned with the forged From, whatever the domain's DMARC policy: an account's forward, a mail rule's forward or copy, a Sieve redirect, an alias or distribution list with an outside member, the mirror copy, a managed-list or journal copy, or a message released from quarantine. A signed copy can also be re-sent to other recipients while the domain's key is unchanged. Exploitation needs DKIM signing to be enabled for the hosted domain (it is off until configured) and, for the forgery to leave the server, a forward, alias, list or rule that carries the domain's mail to an outside address. The signer likewise signed a message submitted over authenticated SMTP as whatever hosted domain its From header named, a header authenticated SMTP does not hold to the submitting account, so that an account of one hosted domain could have mail written in the name of another hosted domain signed with that domain's key; this mattered where the server holds signed-in senders to their own envelope addresses (SmtpAuthenticatedSenderCheck, off by default), as the signature was then the remaining way for such mail to pass the other domain's DMARC policy.2d CVE-2026-1119343.7 LOW

1.9%

——1Coder before 2.34.7 contains an IP spoofing vulnerability in the ExtractRealIPAddress middleware that trusts the leftmost, client-supplied X-Forwarded-For value instead of the client IP appended by a reverse proxy. Attackers can send forged X-Forwarded-For values through appending proxies to bypass per-IP rate limits on login, one-time passcode, and password validation endpoints, enabling brute-force attacks, and to falsify IP addresses recorded in audit logs.3d CVE-2026-1114505.9 MED

2.8%

——1Wheels through 4.1.1 derives its default production error-email address from the Host header of the request that starts the application. If no explicit error-email recipient is configured, a mail server is configured, and the server accepts an attacker-chosen Host, an attacker whose request triggers a cold start can direct later error emails to an address under their control for that application's lifetime. Emails disclose error and request metadata; on engines/versions where scope dumps render, they may also disclose configuration secrets and other users' session/cookie data. On the Lucee 7 engine, scope dumps fail to render, limiting disclosure to header fields. This is fixed in 4.1.2.3d CVE-2026-1114436.5 MED

4.8%

——1Wheels 4.0.6 through 4.1.2 lets an unauthenticated client switch a request into a separate test application context, including in production, by supplying an X-Wheels-Test-Context header or WHEELS_TEST_CONTEXT cookie with any value, or including a test-runner path anywhere in the URL, even the query string. The alternate application uses the same configuration, environment, datasource and debug settings: this is not an authentication bypass or data/debug escalation. It can bypass maintenance mode enabled only at runtime, provide a second set of in-memory rate-limit counters, and trigger additional application-startup side effects and memory use. This is fixed in 4.2.0.6d