Cyber Resilience

CVE-2025-54321

Ascertia Signinghub ≤ 8.6.8

Published
18 November 2025
Modified
20 November 2025
Patch / advisory
View advisory
CVSS Score v3.1 9.8
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0046 38th percentile
Risk Priority 71 floored blend · peak EPSS

Summary

CVE-2025-54321 is a critical-severity Improper Control of Interaction Frequency (CWE-799) vulnerability in Ascertia Signinghub. Its CVSS base score is 9.8 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique Brute Force (T1110); ranked at the 38th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to AC-10 (Concurrent Session Control) and AC-7 (Unsuccessful Logon Attempts) — see the control section below for these in your framework.

OWASP Top 10 for Web (2025)

A06:2025 Insecure Design

EU & UK References

Vulnerability Data

In Ascertia SigningHub through 8.6.8, there is a lack of rate limiting on the reset password function, leading to an email bombing vulnerability. An authenticated attacker can exploit this by automating reset password requests.

CWE(s)
CWE-799

Related Threats

MITRE ATT&CK Enterprise Techniques

T1110 Brute Force Credential Access
Adversaries may use brute force techniques to gain access to accounts when passwords are unknown or when password hashes are obtained.
attack.mitre.org →
T1499.002 Service Exhaustion Flood Impact
Adversaries may target the different network services provided by systems to conduct a denial of service (DoS).
attack.mitre.org →
T1499.003 Application Exhaustion Flood Impact
Adversaries may target resource intensive features of applications to cause a denial of service (DoS), denying availability to those applications.
attack.mitre.org →
T1667 Email Bombing Impact
Adversaries may flood targeted email addresses with an overwhelming volume of messages.
attack.mitre.org →
T1110.001 Password Guessing Credential Access
Adversaries with no prior knowledge of legitimate credentials within the system or environment may guess passwords to attempt access to accounts.
attack.mitre.org →
T1110.003 Password Spraying Credential Access
Adversaries may use a single or small list of commonly used passwords against many different accounts to attempt to acquire valid account credentials.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2025-56221Same product: Ascertia Signinghub
CVE-2025-56224Same product: Ascertia Signinghub
CVE-2025-56223Same product: Ascertia Signinghub
CVE-2025-54320Same product: Ascertia Signinghub
CVE-2025-56219Same product: Ascertia Signinghub
CVE-2025-61166Same product: Ascertia Signinghub
CVE-2025-56218Same product: Ascertia Signinghub
CVE-2023-38068Shared CWE-799
CVE-2026-41333Shared CWE-799
CVE-2024-47654Shared CWE-799

Affected Assets

ascertia
signinghub
≤ 8.6.8

Mitigating Controls

Mitigating Controls (NIST 800-53 r5) AI

AC-10 Concurrent Session Control good match

ac-10 enforces a hard limit on concurrent sessions per user, directly stopping uncontrolled interaction frequency at the session level.

AC-7 Unsuccessful Logon Attempts good match

ac-7 directly enforces a limit on the frequency of invalid authentication attempts, structurally preventing the weakness for that interaction class.

SC-5 Denial-of-service Protection partial match

sc-5 reduces the impact of excessive request volume (DoS) but does not itself impose the frequency controls whose absence defines the weakness.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.IR-01 partial match
prevents

Protecting networks from unauthorized usage can incorporate rate limiting to bound interaction frequency.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

A.8.20 Networks security partial match
mitigates

Network security controls can enforce rate limiting and throttling at the perimeter.

A.8.26 Application security requirements partial match
prevents

Application security requirements explicitly include controls on interaction frequency and throttling.

A.8.27 Secure system architecture and engineering principles partial match
prevents

Secure architecture principles recommend rate-limiting and resource-management mechanisms.

A.8.28 Secure coding partial match
prevents

Secure coding practices can embed input-frequency and throttling checks in code.

A.8.6 Capacity management partial match
degrades

Capacity management directly limits request rates and resource exhaustion that CWE-799 describes.

References