Uncontrolled eviction in the pending sign-in tables of the REST API in Progressive Robot hMailServer 6.3.4 and 6.3.5 allows a remote unauthenticated attacker to make other users' OpenID Connect, SAML and passkey sign-ins fail. The routes that start a single sign-on and hand out a passkey sign-in challenge are reached without authentication and stored pending state in bounded tables that dropped their oldest entry when full, whoever had started it. An attacker who starts sign-ins a few times a second (about a hundred a second for passkeys) pushes every other user's pending sign-in out of the table before that user's browser returns, denying single sign-on and passkey sign-in for as long as the requests continue.
CVE-2026-107585
MEDIUMPre-NVD 5.35.3—Trending — 4 sources updated this week
EchelonGraph scoreHIGH confidence
Score 5.3 from GitHub Security Advisory published 2026-10-08. A secondary CVSS source baseline 5.3; sources differ by 0.0.
Triggered by: GitHub Security Advisory CVSS
Sources: ghsa, secondary
5.3EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
- Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0.4%CVSS: 5.3Exploit: None knownExposed services: Not assessed
No fix is confirmed yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for the fix.
- CVSS v3
- 5.3
- EG Score
- 5.3MEDIUMhigh confidence
- EG Risk
- 39EG Risk 39/100CISA SSVC
EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).
How it’s computedSeverity53% × 45%Exploitation0% × 40%Automatability100% × 15%CISA SSVC: Track at low or medium mission impact; Attend at high (mission-essential systems).Action: No fix is confirmed yet. Restrict network exposure of the affected system or apply the vendor's mitigation within your standard update timelines at low or medium mission impact and sooner than that at high, and watch the vendor's advisory for the fix. - EPSS PROB
- 0.4%
- EPSS %ILE
- 36th
- KEV
- Not listed
CISA SSVCTrack at low or medium mission impact; Attend at high (mission-essential systems).
No fix is confirmed yet. Restrict network exposure of the affected system or apply the vendor's mitigation within your standard update timelines at low or medium mission impact and sooner than that at high, and watch the vendor's advisory for the fix.
Exploitation none (CISA Vulnrichment) · Automatable yes (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). Mission impact is CISA's Mission & Well-being decision point, and only you can judge it: high means the affected system is essential to your organisation's mission, or its compromise could cause irreversible harm to people. CISA's decision table
Published
October 8, 2026
Last Modified
October 8, 2026
Advisory Details (2)
Auto-updated Oct 8, 2026No fix on record yet.
generic
REST API single sign-on and passkey sign-in: an unauthenticated flood of sign-in starts pushed every other person's pending sign-in out (#63) · Issues · hmailserver / hMailServer · GitLab
https://gitlab.com/hmailserver/hmailserver/-/work_items/63generic
hMailServer 6.3.6 · hmailserver / hMailServer · GitLab
https://gitlab.com/hmailserver/hmailserver/-/releases/v6.3.6Vendor Advisories for CVE-2026-107585(1)
These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.
Weakness Classification(1)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 10× in last 7d / 10× in last 30d)
Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.
- 2026-10-09 20:06 UTCEPSS rescore
- 2026-10-09 19:37 UTCGHSA enrichment
- 2026-10-08 21:17 UTCGHSA enrichment
- 2026-10-08 20:20 UTCEG score recompute
- 2026-10-08 20:20 UTCGHSA enrichment
- 2026-10-08 19:26 UTCEG score recompute
- 2026-10-08 19:25 UTCGHSA enrichment
- 2026-10-08 15:20 UTCEG score recompute
- 2026-10-08 15:17 UTCEG score recompute
- 2026-10-08 15:16 UTCMITRE cvelistV5first tracked
Related CVEs(same CWE)
Frequently asked(5)
What is CVE-2026-107585?
CVE-2026-107585 is a medium vulnerability published on October 8, 2026. Uncontrolled eviction in the pending sign-in tables of the REST API in Progressive Robot hMailServer 6.3.4 and 6.3.5 allows a remote unauthenticated attacker to make other users' OpenID Connect, SAML and passkey sign-ins fail. The routes that start a single sign-on and hand out a passkey sign-in…
When was CVE-2026-107585 disclosed?
CVE-2026-107585 was first published on October 8, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-107585 actively exploited?
CVE-2026-107585 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.4% probability of exploitation in the next 30 days (36th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-107585?
CVE-2026-107585 has a CVSS base score of 5.3 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
How do I remediate CVE-2026-107585?
No fix for CVE-2026-107585 is confirmed yet. Until one is published, restrict network exposure of the affected system or apply the vendor's mitigation — for example, keep it off the internet or limit it to trusted networks — and watch the vendor's advisory for the fix. The vendor advisories EchelonGraph has for CVE-2026-107585 are linked in the Vendor Advisories panel on this page.
Dependency Blast Radius
Explore the affected products and dependency analysis for CVE-2026-107585
Is Your Infrastructure Affected by CVE-2026-107585?
EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.