CVE-2025-49591Public exploitNetwork attack vector

Account takeover via encoded path length bypass

Published Jun 18, 2025 · Updated Jun 23, 2025

Improper authentication in CryptPad before 2025.3.0 allows remote authenticated users to access 2FA-protected accounts via crafted URLs. The /block/ middleware in lib/http-worker.js checks the raw path parameter length and skips 2FA when URL encoding makes a 44-character key appear longer. Possession of the account password is required; encoding the key's final character returns the encrypted account block and permits login without the second factor.

CVSS severityUnavailable
Unscored
EPSS probability0.50%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper authentication in CryptPad before 2025.3.0 allows remote authenticated users to access 2FA-protected accounts via crafted URLs. The /block/ middleware in lib/http-worker.js checks the raw path parameter length and skips 2FA when URL encoding makes a 44-character key appear longer. Possession of the account password is required; encoding the key's final character returns the encrypted account block and permits login without the second factor.

The record

CVE
CVE-2025-49591
Published
Jun 18, 2025
Updated
Jun 23, 2025
Vendor
CryptPad
Product
CryptPad
Classifications
CWE-287, CWE-284, T1078
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Jun 18, 2025CVE publishedPublication date reported by the CVE source.
  2. Jun 23, 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?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 2025.3.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

CryptPad · CryptPadversion=< 2025.3.0

Published CVSS scores

7.4GitHub Security AdvisoryCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P

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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-287Improper Authentication
CWE-284Improper Access Control
T1078Valid Accounts

Public exploit references

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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