CVE-2020-15843 json
ActFax Version 7.10 Build 0335 (2020-05-25) is susceptible to a privilege escalation vulnerability due to insecure folder permissions on %P…
published 2020-09-24 6 y ago modified 2026-06-17 4 mo ago also EUVD-2020-7824
- cvss
- 7.3
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.4%
- EPSS 0.4% chance of exploitation in 30 days, percentile 34%
- public exploits
- 0
- none known
Summary
ActFax Version 7.10 Build 0335 (2020-05-25) is susceptible to a privilege escalation vulnerability due to insecure folder permissions on %PROGRAMFILES%\ActiveFax\Client\, %PROGRAMFILES%\ActiveFax\Install\ and %PROGRAMFILES%\ActiveFax\Terminal\. The folder permissions allow "Full Control" to "Everyone". An authenticated local attacker can exploit this to replace the TSClientB.exe binary in the Terminal directory, which is executed on logon for every user. Alternatively, the attacker can replace any of the binaries in the Client or Install directories. The latter requires additional user interaction, for example starting the client.
Exploit prediction
0.40% chance of exploitation in the next 30 days, higher than 34% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- blog.to.com https://blog.to.com/advisory-actfax-7-10-build-0335-privilege-escalation-cve-2020-15843/ referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| NVD | 3.1 | 7.3 | CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H |
| NVD | 2.0 | 4.4 | AV:L/AC:M/Au:N/C:P/I:P/A:P |
Classification
- Weakness
-
- CWE-276 Incorrect Default Permissions
References
-
blog.to.com
/advisory-actfax-7-10-build-0335-privilege-escalation-cve-2020-15843/
exploit, third-party-advisory
Sources
- CVE List CVE-2020-15843
- NVD CVE-2020-15843
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