Progressive Robot hMailServer up to 6.3.5 Pending Sign-in Tables state issue

CVSS Meta Temp Score
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CTI Interest Score
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4.7$0-$5k2.20-

Summaryinfo

A vulnerability marked as problematic has been reported in Progressive Robot hMailServer up to 6.3.5. This affects an unknown part of the component Pending Sign-in Tables. Performing a manipulation results in state issue. This vulnerability is identified as CVE-2026-107585. The attack can be initiated remotely. There is not any exploit available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as problematic, was found in Progressive Robot hMailServer up to 6.3.5. This affects an unknown code of the component Pending Sign-in Tables. The manipulation with an unknown input leads to a state issue vulnerability. CWE is classifying the issue as CWE-371. This is going to have an impact on availability. The summary by CVE is:

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.

The advisory is shared at gitlab.com. This vulnerability is uniquely identified as CVE-2026-107585 since 10/08/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. It demands that the victim is doing some kind of user interaction. Neither technical details nor an exploit are publicly available.

Upgrading to version 6.3.6 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-95037). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

Type

Vendor

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.8
VulDB Meta Temp Score: 4.7

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 5.3
CNA Vector (GitLab): 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: State issue
CWE: CWE-371
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: hMailServer 6.3.6

Timelineinfo

10/08/2026 Advisory disclosed
10/08/2026 +0 days CVE reserved
10/08/2026 +0 days VulDB entry created
10/08/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: gitlab.com
Status: Confirmed

CVE: CVE-2026-107585 (🔒)
GCVE (CVE): GCVE-0-2026-107585
GCVE (VulDB): GCVE-100-415461
EUVD: 🔒

Entryinfo

Created: 10/08/2026 17:29
Updated: 10/08/2026 18:32
Changes: 10/08/2026 17:29 (64), 10/08/2026 18:32 (1)
Complete: 🔍
Cache ID: 216::103

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

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