CVE-2025-51846
CryptPad unbounded WebSocket frame flood
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
CryptPad unbounded WebSocket frame flood
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.
- Record
CVE-2025-51846- CVSS 4.0
- 8.7 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N - CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-770
- Updated
- 2026-11-02
EUVDEUVD-2025-209596
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.
- Record
EUVD-2025-209596- CVSS 4.0
- 8.7 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-jmrh-f3j8-q3c4
CryptPad 2025.3.1 allows unbounded WebSocket frame flood. A remote, unauthenticated attacker can...
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.
- Record
GHSA-jmrh-f3j8-q3c4- CVSS 4.0
- 8.7 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-770
- Updated
- 2026-11-02
NVD
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.
- Record
CVE-2025-51846- CVSS 4.0
- 8.7 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-770
- Updated
- 2026-11-02
OSV
CryptPad unbounded WebSocket frame flood
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.
- Record
CVE-2025-51846- CVSS 4.0
- 8.7 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N - Weakness
- CWE-770
- Updated
- 2026-11-02
Affected products
Public exploits
Links only. Every CVE stores no exploit code.
| Source | Link | Date |
|---|---|---|
| PoC in GitHub | JohnPerifanis/cryptpad-cve-2025-51846-advisory | 2026-04-22 |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV, PoC in GitHub |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2025-51846 is a high vulnerability (CVSS 8.7) in Cryptpad, published April 30, 2026. Public exploit code exists. EPSS puts the chance of exploitation in the next 30 days at 0.58%, the 47th percentile. No source names a fixed version.
References
github.com/cryptpad/cryptpad/pull/2239/changes/1e0c06ad8a0c5dab795f85f9730ec2693320c62e
cve.org/CVERecord?id=CVE-2025-51846
raw.githubusercontent.com/cisagov/CSAF/develop/csaf_files/IT/white/2026/va-26-119-01.json
nvd.nist.gov/vuln/detail/CVE-2025-51846