CVE-2021-32816 json
Regular expression Denial of Service in ProtonMail
published 2021-05-14 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-19566
- cvss
- 6.5
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 1.0%
- EPSS 1.0% chance of exploitation in 30 days, percentile 63%
- public exploits
- 0
- none known
Summary
ProtonMail Web Client is the official AngularJS web client for the ProtonMail secure email service. ProtonMail Web Client before version 3.16.60 has a regular expression denial-of-service vulnerability. This was fixed in commit 6687fb. There is a full report available in the referenced GHSL-2021-027.
Patch / fix
Exploit prediction
1.01% chance of exploitation in the next 30 days, higher than 63% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- securitylab.github.com https://securitylab.github.com/advisories/GHSL-2021-027-redos-ProtonMail/ referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 6.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H |
| NVD | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| NVD | 2.0 | 5.0 | AV:N/AC:L/Au:N/C:N/I:N/A:P |
Affected products
- ProtonMail WebClient
Classification
- Weakness
-
- CWE-400 Uncontrolled Resource Consumption
References
-
github.com
/ProtonMail/WebClient/commit/6687fbb867ef872c96cf4fde68cb6e9c58d3fddc
patch, third-party-advisory
-
securitylab.github.com
/advisories/GHSL-2021-027-redos-ProtonMail/
exploit, third-party-advisory
Sources
- CVE List CVE-2021-32816
- NVD CVE-2021-32816
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