CVE-2026-126623
waiting for further signalsZero needs more public information before it can validate it.GHSA-gxm7-28h3-vf9j ↗EUVD-2026-123328 ↗
description
hMailServer 6.3.6 and 6.3.7 can spend excessive CPU time parsing specially chosen JSON objects, allowing remote attackers to occupy mail-delivery or REST API workers and disrupt mail, webmail, or API availability. Unauthenticated exposure depends on configured TLS-RPT report mailboxes or on enabling the REST API with public password-protected-message links.
mitigation
Disable the REST API and public password-protected-message links where they are not required, and remove or isolate TLS-RPT report mailbox handling where operationally feasible. Restrict access to JSON-processing webmail and API routes and apply request-size or rate controls at a proxy; no fixed version is recorded in the advisory.
outcome
No artifact: an exploit or check was attempted but could not be produced at this moment.
source signals
Public signals that triggered or updated the pipeline. These are inputs for the deltas above.
- 2026-11-11 08:31Zcve_org: trigger signal, started the run
this entry in the feed
GET /api/v1/feed/CVE-2026-126623
{ "etk_id": "ETK-2026-4153", "cve_id": "CVE-2026-126623", "display_id": "CVE-2026-126623", "ghsa_id": "GHSA-gxm7-28h3-vf9j", "euvd_id": "EUVD-2026-123328", "status": "published", "anchor_state": "anchored", "title": "Algorithmic-complexity denial of service in hMailServer JSON parsing", "summary": "hMailServer 6.3.6 and 6.3.7 can spend excessive CPU time parsing specially chosen JSON objects, allowing remote attackers to occupy mail-delivery or REST API workers and disrupt mail, webmail, or API availability. Unauthenticated exposure depends on configured TLS-RPT report mailboxes or on enabling the REST API with public password-protected-message links.", "mitigation": "Disable the REST API and public password-protected-message links where they are not required, and remove or isolate TLS-RPT report mailbox handling where operationally feasible. Restrict access to JSON-processing webmail and API routes and apply request-size or rate controls at a proxy; no fixed version is recorded in the advisory.", "vendor": "Progressive Robot Ltd", "product": "hMailServer", "affected": [ { "affected_notes": [], "affected_ranges": [ ">= 6.3.6, <= 6.3.7" ], "ecosystem": null, "fixed_versions": [], "package_name": "hMailServer", "purl": null } ], "cwes": [ 407 ], "cvss_score": 7.5, "cvss_src": "cna_vendor", "cvss_vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "epss_score": null, "epss_percentile": null, "epss_asof": null, "automation": "deterministic", "check": false, "check_confidence_basis": null, "exploit": false, "pipeline_minutes": 138.21308618333333, "t0_at": "2026-11-11T08:31:47.129000+00:00", "signals": { "trigger_signal": { "at": "2026-11-11T08:31:47.129000+00:00", "days": 0, "is_lower_bound": false, "measured_at": "2026-11-11T08:31:47.129000+00:00", "url": "https://www.cve.org/CVERecord?id=CVE-2026-126623" } } }
published 2026-11-11 08:47Z
last change 2026-11-11 12:45Z
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