Arbitrary file upload in Veritas Backup Exec

CVE-2020-36167

An issue was discovered in the server in Veritas Backup Exec through 16.2, 20.6 before hotfix 298543, and 21.1 before hotfix 657517. On start-up, it loads the OpenSSL library from the Installation folder. This library in turn attempts to load the /usr/local/ssl/openssl.cnf configuration file, which may not exist. On Windows systems, this path could translate to <drive>:\usr\local\ssl\openssl.cnf. A low privileged user can create a :\usr\local\ssl\openssl.cnf configuration file to load a malicious OpenSSL engine, resulting in arbitrary code execution as SYSTEM when the service starts. This gives the attacker administrator access on the system, allowing the attacker (by default) to access all data, access all installed applications, etc. If the system is also an Active Directory domain controller, then this can affect the entire domain.

Vulnerability class: Unrestricted File Upload

Published · last modified .

CVSS v3 metric

CVSS v3 base score 9.3 (Critical). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.005 (37.6th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 38th percentile — 37.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2020-36167: held from 0.005 to 0.005.

EPSS over last 30 days · oldest: 0.005 · newest: 0.005 · change: 0.000

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2020-36167?
CVE-2020-36167 is a critical-severity vulnerability in Veritas Backup Exec, classified under Unrestricted Upload of File with Dangerous Type. CVSS score: 9.3/10. Published 2021-01-06.
How severe is CVE-2020-36167?
Critical severity. CVSS v3 base score is 9.3 out of 10.
Is CVE-2020-36167 known to be exploited?
2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.