CVE-2021-39271

Severity: high (CVSS 8.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 3.7% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2021-08-30 · updated 2026-06-17

Description

OrbiTeam BSCW Classic before 7.4.3 allows authenticated remote code execution (RCE) during archive extraction via attacker-supplied Python code in the class attribute of a .bscw file. This is fixed in 5.0.12, 5.1.10, 5.2.4, 7.3.3, and 7.4.3.

Affected products

Bscw Classic: before 5.0.12; from 5.1.0 before 5.1.10; from 5.2.0 before 5.2.4; from 7.3.0 before 7.3.3; from 7.4.0 before 7.4.3 — fixed in 5.0.12, 5.1.10, 5.2.4, 7.3.3, 7.4.3

How to fix

Upgrade to a fixed version: Bscw Classic 5.0.12, 5.1.10, 5.2.4, 7.3.3. Check the vendor advisory for mitigations.

References

http://packetstormsecurity.com/files/163989/BSCW-Server-Remote-Code-Execution.html
https://seclists.org/fulldisclosure/2021/Aug/24
https://www.bscw.de/en/company/
http://packetstormsecurity.com/files/163989/BSCW-Server-Remote-Code-Execution.html
https://seclists.org/fulldisclosure/2021/Aug/24
https://www.bscw.de/en/company/

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