CVE-2021-34418 json
Pre-auth Null pointer crash in on-premise web console
published 2021-11-11 4 y ago modified 2026-06-17 4 mo ago also EUVD-2021-21076
- cvss
- 4.0
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.6%
- EPSS 0.6% chance of exploitation in 30 days, percentile 50%
- public exploits
- 0
- none known
Summary
The login routine of the web console in the Zoom On-Premise Meeting Connector before version 4.6.239.20200613, Zoom On-Premise Meeting Connector MMR before version 4.6.239.20200613, Zoom On-Premise Recording Connector before version 3.8.42.20200905, Zoom On-Premise Virtual Room Connector before version 4.4.6344.20200612, and Zoom On-Premise Virtual Room Connector Load Balancer before version 2.5.5492.20200616 fails to validate that a NULL byte was sent while authenticating. This could lead to a crash of the login service.
Patch / fix
- Zoom Video Communications Inc Zoom On-Premise Meeting Connector 4.6.239.20200613
- Zoom Video Communications Inc Zoom On-Premise Meeting Connector MMR 4.6.239.20200613
- Zoom Video Communications Inc Zoom On-Premise Recording Connector 3.8.42.20200905
- Zoom Video Communications Inc Zoom On-Premise Virtual Room Connector 4.4.6344.20200612
- Zoom Video Communications Inc Zoom On-Premise Virtual Room Connector Load Balancer 2.5.5492.20200616
Exploit prediction
0.63% chance of exploitation in the next 30 days, higher than 50% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 4.0 | CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L |
| NVD | 3.1 | 5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L |
| NVD | 2.0 | 5.0 | AV:N/AC:L/Au:N/C:N/I:N/A:P |
Affected products
- Zoom Video Communications Inc Zoom On-Premise Meeting Connector
- Zoom Video Communications Inc Zoom On-Premise Meeting Connector MMR
- Zoom Video Communications Inc Zoom On-Premise Recording Connector
- Zoom Video Communications Inc Zoom On-Premise Virtual Room Connector
- Zoom Video Communications Inc Zoom On-Premise Virtual Room Connector Load Balancer
Classification
- Weakness
-
- CWE-476 NULL Pointer Dereference
References
-
explore.zoom.us
/en/trust/security/security-bulletin
vendor-advisory
Sources
- CVE List CVE-2021-34418
- NVD CVE-2021-34418
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.