CVE-2021-21387
HIGHDescription
Wrongthink peer-to-peer, end-to-end encrypted messenger with PeerJS and Axolotl ratchet. In wrongthink from version 2.0.0 and before 2.3.0 there was a set of vulnerabilities causing inadequate encryption strength. Part of the secret identity key was disclosed by the fingerprint used for connection. Additionally, the safety number was improperly calculated. It was computed using part of one of the public identity keys instead of being derived from both public identity keys. This caused issues in computing safety numbers which would potentially be exploitable in the real world. Additionally there was inadequate encryption strength due to use of 1024-bit DSA keys. These issues are all fixed in version 2.3.0.
How to fix
TridentStack Control can deploy fixes like this automatically across your Windows, macOS, and Linux fleet. See how it works
Remediation is compiled from vendor and distribution security advisories. Always confirm against the linked source for your exact version and platform.
CVSS v3 Vector
Exploitability
Impact
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N
Exploit Intelligence
Low risk: more likely to be exploited than 32% of all known CVEs.
References
Related Vulnerabilities
Other CWE-319 vulnerabilities, ordered by exploit likelihood. View all
| CVE | Severity | CVSS | EPSS | Exploited | Fix |
|---|---|---|---|---|---|
| CVE-2018-12710 | High | 8.0 | 77% | - | - |
| CVE-2024-25735 | Critical | 9.1 | 51% | - | Fix |
| CVE-2019-3993 | High | 7.5 | 46% | - | - |
| CVE-2017-5259 | High | 8.8 | 39% | - | - |
| CVE-2016-5649 | Critical | 9.8 | 27% | - | - |
| CVE-2021-39341 | High | 8.2 | 22% | - | - |
Common questions
How do I fix CVE-2021-21387?
Upgrade wrongthink to 2.3.0 or later.
Is CVE-2021-21387 being actively exploited?
Not that we know of. CVE-2021-21387 is not in the CISA Known Exploited Vulnerabilities catalog. Its EPSS score of 0.40% is the estimated probability that it will be exploited in the next 30 days. That is higher than 32% of all scored CVEs.
How severe is CVE-2021-21387?
CVE-2021-21387 has a CVSS v3 base score of 8.1, rated high. CVSS rates the technical impact if the vulnerability is exploited, not how likely that is, so weigh it alongside the exploit-prediction score when you decide what to patch first.
What does CVE-2021-21387 affect?
Published advisories record a fix for wrongthink (NVD). Only products with a sourced advisory are listed, so treat this as what we can cite rather than a complete inventory.
Embed a live status badge for CVE-2021-21387
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TridentStack Control continuously scans your Windows, macOS, and Linux fleet for known vulnerabilities, prioritizes them by severity and active exploitation, and patches them automatically.
This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2024-11-21.