CVE-2025-43931

Auth Bypass

Published

07 July 2025

Modified

17 June 2026

CVSS Score v3.1 9.8

Click a component to see what it means

Raw vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS Score 0.0034 27th percentile

Risk Priority 70 floored blend · peak EPSS

Summary

CVE-2025-43931 is a critical-severity Weak Password Recovery Mechanism for Forgotten Password (CWE-640) vulnerability. Its CVSS base score is 9.8 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique Valid Accounts (T1078); ranked at the 27th 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 IA-12 (Identity Proofing) and IA-5 (Authenticator Management) — see the control section below for these in your framework.

OWASP Top 10 for Web (2025)

EU & UK References

🇪🇺 ENISA EUVD: EUVD-2025-20241

Vulnerability Data

flask-boilerplate through a170e7c allows account takeover via the password reset feature because SERVER_NAME is not configured and thus a reset depends on the Host HTTP header.

CWE(s): CWE-640

Related Threats

MITRE ATT&CK Enterprise Techniques

T1078 Valid Accounts Stealth

Adversaries may obtain and abuse credentials of existing accounts as a means of gaining Initial Access, Persistence, Privilege Escalation, or Defense Evasion.

attack.mitre.org →

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 →

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 →

Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2024-0186Shared CWE-640

CVE-2025-50433Shared CWE-640

CVE-2023-43650Shared CWE-640

CVE-2026-9273Shared CWE-640

CVE-2026-9609Shared CWE-640

CVE-2023-42481Shared CWE-640

CVE-2026-7655Shared CWE-640

CVE-2024-9907Shared CWE-640

CVE-2023-35717Shared CWE-640

CVE-2026-15155Shared CWE-640

Affected Assets

Mitigating Controls

Control response

Prevent

Stop it (NIST 800-53)

—

Detect

Catch it (NIST detect / respond)

—

Harden

Shrink the surface (DISA STIG)

—

Validate

Prove the fix (OWASP ASVS)

V7.4.3

Mitigating Controls (NIST 800-53 r5) AI

IA-12 Identity Proofing good match

Identity proofing at appropriate assurance levels ensures forgotten-password recovery cannot succeed without strong verification of the user.

IA-5 Authenticator Management good match

Authenticator management requires secure distribution, reset, and verification procedures that directly address weak password recovery flows.

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.AA-01 mostly match

prevents

Credential lifecycle management directly includes password reset/recovery flows.

PR.AA-02 mostly match

prevents

Identity proofing is the core control that prevents weak or bypassed recovery mechanisms.

PR.AA-03 partial match

prevents

Authentication policy covers strength/MFA but does not address recovery path weaknesses.

PR.PS-06 partial match

prevents

Secure SDLC reduces implementation flaws but is not specific to password-recovery design.

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.5.17 Authentication information partial match

degrades

Strong authentication-information lifecycle rules directly address weak password-recovery flows.

A.8.25 Secure development life cycle partial match

prevents

Secure-SDLC practices can embed strong recovery design, yet the control is broader than this single weakness.

A.8.26 Application security requirements partial match

prevents

Application-security requirements can mandate secure recovery flows, but the control covers many other requirements.

A.8.28 Secure coding partial match

prevents

Secure-coding standards can prevent weak recovery implementations, yet the control is wider in scope.

A.8.5 Secure authentication partial match

mitigates

Secure-authentication requirements include robust forgotten-password procedures.

A.5.18 Access rights none match

none

Proper access-rights provisioning can limit who can trigger recovery, but does not fix the recovery mechanism itself.