CVE-2025-56221Network attack vector

Account compromise via unlimited password guessing

Published Oct 17, 2025 · Updated Oct 17, 2025

Improper login-attempt restriction in Ascertia SigningHub 8.6.8 allows remote attackers to access accounts through password guessing. The /authenticate API accepts unlimited repeated password attempts without rate limiting, a cooldown period, or account lockout. Network reachability to that API and a successfully guessed valid password are required; access is limited to the targeted account's privileges.

CVSS severity9.8
Critical
EPSS probability0.56%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper login-attempt restriction in Ascertia SigningHub 8.6.8 allows remote attackers to access accounts through password guessing. The /authenticate API accepts unlimited repeated password attempts without rate limiting, a cooldown period, or account lockout. Network reachability to that API and a successfully guessed valid password are required; access is limited to the targeted account's privileges.

The record

CVE
CVE-2025-56221
Published
Oct 17, 2025
Updated
Oct 17, 2025
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-307, T1110.001
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Oct 17, 2025CVE publishedPublication date reported by the CVE source.
  2. Oct 17, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

9.8CISA-ADPCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-307Improper Restriction of Excessive Authentication Attempts
T1110.001Brute Force: Password Guessing

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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