CVE-2026-103647
validatedZero produced an exploit or a check.GHSA-xr9h-mj6v-hm4m ↗EUVD-2026-94836 ↗
description
hMailServer 6.3.2 through 6.3.5 webmail can render a decrypted encrypted-message attachment in the webmail security context. An attacker who can send such a message may run script with the recipient's webmail session if the recipient opens the attachment in a new tab; webmail exposure requires the REST API to be enabled.
mitigation
Upgrade hMailServer to 6.3.6. Until the upgrade is complete, disable the REST API to prevent webmail from being served.
fixed in 6.3.6
outcome
Check only, differential: the check fires on the vulnerable build and is silent on the patched one.
source signals
Public signals that triggered or updated the pipeline. These are inputs for the deltas above.
- 2026-10-08 10:53Zcve_org: trigger signal, started the run
this entry in the feed
GET /api/v1/feed/CVE-2026-103647
{ "etk_id": "ETK-2026-966", "cve_id": "CVE-2026-103647", "display_id": "CVE-2026-103647", "ghsa_id": "GHSA-xr9h-mj6v-hm4m", "euvd_id": "EUVD-2026-94836", "status": "published", "anchor_state": "anchored", "title": "Cross-site scripting in hMailServer webmail attachments", "summary": "hMailServer 6.3.2 through 6.3.5 webmail can render a decrypted encrypted-message attachment in the webmail security context. An attacker who can send such a message may run script with the recipient's webmail session if the recipient opens the attachment in a new tab; webmail exposure requires the REST API to be enabled.", "mitigation": "Upgrade hMailServer to 6.3.6. Until the upgrade is complete, disable the REST API to prevent webmail from being served.", "vendor": "Progressive Robot Ltd", "product": "hMailServer", "affected": [ { "affected_notes": [], "affected_ranges": [ ">= 6.3.2, < 6.3.6" ], "ecosystem": null, "fixed_versions": [ "6.3.6" ], "package_name": "hMailServer", "purl": null } ], "cwes": [ 79 ], "cvss_score": 8, "cvss_src": "cna_vendor", "cvss_vector": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:N", "epss_score": 0.0025, "epss_percentile": 0.1497, "epss_asof": "2026-10-20", "automation": "deterministic", "check": true, "check_confidence_basis": "differential", "exploit": false, "pipeline_minutes": 47.8155174, "t0_at": "2026-10-08T10:53:05.628000+00:00", "signals": { "check": { "at": "2026-10-08T12:24:22.544141+00:00", "days": 0.06339023311342593, "is_lower_bound": false, "measured_at": "2026-10-08T10:53:05.628000+00:00", "url": null }, "trigger_signal": { "at": "2026-10-08T10:53:05.628000+00:00", "days": 0, "is_lower_bound": false, "measured_at": "2026-10-08T10:53:05.628000+00:00", "url": "https://www.cve.org/CVERecord?id=CVE-2026-103647" } } }
published 2026-10-08 11:36Z
last change 2026-10-21 04:45Z
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