critical Known exploitedREV. 01

CVE-2020-12641Roundcube — image settings that reach a command line

Roundcube before 1.4.4 lets shell characters in the image conversion settings reach a command line, so whoever can change that configuration runs code on the mail server itself.

YOUR NEXT MOVE

Update Roundcube to 1.4.4 or later, and check who can edit the instance configuration — the setting this abuses is an administrative one.

Read the risk

THE VITAL STATS
CVSS score
9.8/ 10
CVSS v3.1
EPSS probability
84%
Likelihood of exploitation
Attack complexity
Low
Conditions needed to exploit
Known exploited
Yes — CISA KEV
CVE published
2020-05-04
Added to KEV
2023-06-22
Exploit published
Yes
Confidence
high
Kill chain
execution
MITRE ATT&CK
T1059
Severity
critical

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Attacker needsThe attacker must be able to set the instance's image conversion configuration.

Fixed inRoundcube Webmail >= 1.4.4

Behind the card

5 REFERENCES
Field-level provenanceTRACE THE SOURCES +

Which source supports each field, when it was retrieved, and who extracted it.

FieldsSourceRetrievedExtractorConfidence
cvss, exploitation.attack_complexity, exploitation.exploit_available, references, published_atnvd.nist.gov2026-09-24scrty-crds-pipeline/0.1high
exploitation.known_exploited, exploitation.kev_addedcisa.gov2026-09-24scrty-crds-pipeline/0.1high
epssapi.first.org2026-09-24scrty-crds-pipeline/0.1high
title, summary, severity, remediation, mitre_attack, kill_chain, recommended_action, confidence, tags, exploitation.prerequisitesnvd.nist.gov2026-09-24claude-codehigh

Printing history

THE RECORD
  1. r1Initial base card

First printing. This card has not been reprinted since publication.

crds:cve-2020-12641 · CRDS 0.1 · Issued 2026-09-24