Arbitrary file upload in Synacor Zimbra Collaboration Suite

CVE-2020-12846

Zimbra before 8.8.15 Patch 10 and 9.x before 9.0.0 Patch 3 allows remote code execution via an avatar file. There is potential abuse of /service/upload servlet in the webmail subsystem. A user can upload executable files (exe,sh,bat,jar) in the Contact section of the mailbox as an avatar image for a contact. A user will receive a "Corrupt File" error, but the file is still uploaded and stored locally in /opt/zimbra/data/tmp/upload/, leaving it open to possible remote execution.

Vulnerability class: Unrestricted File Upload

Published · last modified .

CVSS v3 metric

CVSS v3 base score 8.0 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.026 (84.9th percentile), scored .

Low probability of exploitation in the next 30 days, but still tracked. 85th percentile — 84.9% 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-2020-12846: held from 0.026 to 0.026.

EPSS over last 30 days · oldest: 0.026 · newest: 0.026 · change: 0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2020-12846?
CVE-2020-12846 is a high-severity vulnerability in Synacor Zimbra Collaboration Suite, classified under Unrestricted Upload of File with Dangerous Type. CVSS score: 8.0/10. Published 2020-06-03.
How severe is CVE-2020-12846?
High severity. CVSS v3 base score is 8.0 out of 10.