CVE-2021-21387
Partial secret key disclosure, improper safety number calculation, & inadequate encryption strength
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- Required
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
Partial secret key disclosure, improper safety number calculation, & inadequate encryption strength
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.
- Record
CVE-2021-21387- CVSS 3.1
- 8.1 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N - Weakness
- CWE-319, CWE-326, CWE-358
- Updated
- 2026-11-02
EUVDEUVD-2021-8691
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.
- Record
EUVD-2021-8691- CVSS 3.1
- 8.1 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N - Updated
- 2026-11-03
NVD
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.
- Record
CVE-2021-21387- CVSS 3.1
- 8.1 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N - CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N - CVSS 2.0
- 5.0 Medium
AV:N/AC:L/Au:N/C:P/I:N/A:N - Weakness
- CWE-319, CWE-326, CWE-358
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases, products | EUVD | |
| first indexed | CVE List, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2021-21387 is a high vulnerability (CVSS 8.1) in Birb-digital Wrongthink, published March 19, 2021. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.39%, the 33rd percentile. No source names a fixed version.