Führe statische Analyse (SAST) auf der Codebasis aus und suche im Datenfluss nach dem unsicheren Muster.
CWE-620 Base Draft
Unverified Password Change
This vulnerability occurs when an application allows a user to set a new password without first verifying their identity through the old password or a secure secondary authentication method.
Definition
What is CWE-620?
This vulnerability occurs when an application allows a user to set a new password without first verifying their identity through the old password or a secure secondary authentication method.
This flaw creates a major security gap, as an attacker who can access the password change function (for example, through a predictable user ID or a cross-site request forgery attack) can reset another user's credentials. Without proper verification, the system implicitly trusts that the person requesting the change is the legitimate account holder, leading to a complete account takeover.
To prevent this, developers must always require proof of identity before processing a password reset. The standard practice is to require the user's current password for a voluntary change, or to use a time-limited, single-use token sent to a pre-verified email or phone for a recovery scenario. This ensures that control of the account is never relinquished based on a simple request alone.
Auswirkungen in der Praxis
Real-world CVEs caused by CWE-620
-
Web app allows remote attackers to change the passwords of arbitrary users without providing the original password, and possibly perform other unauthorized actions.
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Web application password change utility doesn't check the original password.
Wie Angreifer es ausnutzen
Angreiferpfad Schritt für Schritt
- 1
Identifiziere einen Codepfad, der nicht vertrauenswürdige Eingaben ohne Validierung verarbeitet.
- 2
Erzeuge eine Payload, die das unsichere Verhalten auslöst — Injection, Traversal, Overflow oder Logik-Missbrauch.
- 3
Liefere die Payload über einen normalen Request aus und beobachte die Reaktion der Anwendung.
- 4
Iteriere, bis die Antwort Daten preisgibt, Angreifer-Code ausführt oder Berechtigungen eskaliert.
Verwundbares Codebeispiel
Vulnerable PHP
This code changes a user's password.
$user = $_GET['user'];
$pass = $_GET['pass'];
$checkpass = $_GET['checkpass'];
if ($pass == $checkpass) {
SetUserPassword($user, $pass);
} Sicheres Codebeispiel
Secure pseudo
// Validate, sanitize, or use a safe API before reaching the sink.
function handleRequest(input) {
const safe = validateAndEscape(input);
return executeWithGuards(safe);
} What changed: the unsafe sink is replaced (or the input is validated/escaped) so the same payload no longer triggers the weakness.
Präventions-Checkliste
How to prevent CWE-620
- Architecture and Design When prompting for a password change, force the user to provide the original password in addition to the new password.
- Architecture and Design Do not use "forgotten password" functionality. But if you must, ensure that you are only providing information to the actual user, e.g. by using an email address or challenge question that the legitimate user already provided in the past; do not allow the current user to change this identity information until the correct password has been provided.
Erkennungssignale
How to detect CWE-620
Führe dynamische Application-Security-Tests gegen den Live-Endpoint aus.
Beobachte Runtime-Logs auf ungewöhnliche Exception-Traces, fehlerhafte Eingaben oder Versuche, Autorisierung zu umgehen.
Code Review: Markiere jeden neuen Code, der Eingaben von dieser Oberfläche ohne validierte Framework-Helper verarbeitet.
CWE-620
Don't catalog this weakness. Prove it's reachable.
Plexicus turns CWE catalogs into evidence: every CWE-pattern is matched against your real code graph, reach is proven on a sandbox clone, and verified findings ship as reviewed PRs.
Häufig gestellte Fragen Was ist CWE-620?
Wie gravierend ist CWE-620?
Welche Sprachen oder Plattformen sind von CWE-620 betroffen?
Wie kann ich CWE-620 verhindern?
Wie erkennt und behebt Plexicus CWE-620?
Wo erfahre ich mehr über CWE-620?
Frequently asked questions
Was ist CWE-620?
This vulnerability occurs when an application allows a user to set a new password without first verifying their identity through the old password or a secure secondary authentication method.
Wie gravierend ist CWE-620?
MITRE hat für diese Schwachstelle keine Exploit-Wahrscheinlichkeit veröffentlicht. Behandle sie als mittlere Auswirkung, bis dein Threat Model anderes belegt.
Welche Sprachen oder Plattformen sind von CWE-620 betroffen?
MITRE hat für diese CWE keine betroffenen Plattformen spezifiziert — sie kann in den meisten Anwendungs-Stacks auftreten.
Wie kann ich CWE-620 verhindern?
When prompting for a password change, force the user to provide the original password in addition to the new password. Do not use "forgotten password" functionality. But if you must, ensure that you are only providing information to the actual user, e.g. by using an email address or challenge question that the legitimate user already provided in the past; do not allow the current user to change this identity information until the correct password has been provided.
Wie erkennt und behebt Plexicus CWE-620?
Die SAST-Engine von Plexicus erkennt die Datenfluss-Signatur von CWE-620 bei jedem Commit. Bei einem Treffer öffnet unser Codex-Remedium-Agent einen Fix-PR mit korrigiertem Code, Tests und einer einzeiligen Zusammenfassung für den Reviewer.
Wo erfahre ich mehr über CWE-620?
MITRE veröffentlicht die kanonische Definition unter https://cwe.mitre.org/data/definitions/620.html. Für ergänzende Hinweise kannst du auch die OWASP- und NIST-Dokumentation heranziehen.
Verwandte Schwachstellen
Weaknesses related to CWE-620
CWE-1390 Parent
Weak Authentication
This vulnerability occurs when a system's login or identity verification process is too easy to bypass or fool. While it attempts to check…
CWE-1391 Sibling
Use of Weak Credentials
This vulnerability occurs when a system relies on weak authentication credentials—like default passwords, hard-coded keys, or easily…
CWE-262 Sibling
Not Using Password Aging
This vulnerability occurs when a system lacks password expiration policies, allowing users to keep the same password indefinitely.
CWE-263 Sibling
Password Aging with Long Expiration
The system enforces password changes, but the time allowed between changes is excessively long, weakening security.
CWE-289 Sibling
Authentication Bypass by Alternate Name
This vulnerability occurs when a system checks access based on a resource or user name, but fails to account for all the different names…
CWE-290 Sibling
Authentication Bypass by Spoofing
This weakness occurs when an application's authentication system can be tricked into accepting forged or manipulated credentials, allowing…
CWE-294 Sibling
Authentication Bypass by Capture-replay
This vulnerability occurs when an attacker can intercept and record legitimate authentication traffic, then replay it later to gain…
CWE-301 Sibling
Reflection Attack in an Authentication Protocol
A reflection attack is a flaw in mutual authentication protocols that allows an attacker to impersonate a legitimate user without knowing…
CWE-302 Sibling
Authentication Bypass by Assumed-Immutable Data
This vulnerability occurs when an authentication system incorrectly treats certain data as unchangeable, when in fact an attacker can…
Ressourcen
Further reading
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Bereit zu validieren, was zählt.
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