High severity · published Apr 30, 2026
CVE-2025-51846
CryptPad unbounded WebSocket frame flood
7.5
CVSS
0.6%
EPSS
No
On KEV
Description
CryptPad 2025.3.1 allows unbounded WebSocket frame flood. A remote, unauthenticated attacker can significantly degrade or deny service for all users of a CryptPad instance. Fixed in 2026.2.2.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.6% · higher than 47% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CR
CryptPad · CryptPad
2025.3.1 before 2026.2.2 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-51846
CVE.org
https://www.cve.org/CVERecord?id=CVE-2025-51846
Exploit
https://github.com/JohnPerifanis/cryptpad-cve-2025-51846-advisory/blob/main/README.md
Patch
https://github.com/cryptpad/cryptpad/pull/2239/changes/1e0c06ad8a0c5dab795f85f9730ec2693320c62e
Third Party Advisory
https://raw.githubusercontent.com/cisagov/CSAF/develop/csaf_files/IT/white/2026/va-26-119-01.json
Third Party Advisory
https://www.cve.org/CVERecord?id=CVE-2025-51846
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