Is CVE-2016-9920 in the CISA KEV catalog?

No. CVE-2016-9920 is not currently on the CISA Known Exploited Vulnerabilities list.

What is the CVSS severity of CVE-2016-9920?

CVE-2016-9920 has a CVSS v3 base score of 7.5 (HIGH).

What is the EPSS score for CVE-2016-9920?

CVE-2016-9920 has an EPSS score of 5.62% (92th percentile), estimating the probability of exploitation in the next 30 days.

How do I fix CVE-2016-9920?

Upgrade roundcube on debian 11 to 1.2.3+dfsg.1-1 or later. Fixes are available for 4 affected products.

CVE & CISA-KEV Catalog

CVE-2016-9920

HIGHEPSS 92th pctl

7.5

CVSS v3

NVD

Description

steps/mail/sendmail.inc in Roundcube before 1.1.7 and 1.2.x before 1.2.3, when no SMTP server is configured and the sendmail program is enabled, does not properly restrict the use of custom envelope-from addresses on the sendmail command line, which allows remote authenticated users to execute arbitrary code via a modified HTTP request that sends a crafted e-mail message.

CWE-284Improper Access Control

How to fix

Remediation Available

roundcubeDebian

Fixed in:1.2.3+dfsg.1-1CVE-2016-9920

roundcubeUbuntu

Fixed in:1.2~beta+dfsg.1-0ubuntu1+esm7USN-8132-1

Fixed in:1.3.6+dfsg.1-1ubuntu0.1~esm7USN-8132-1

roundcube-coreUbuntu

Fixed in:1.2~beta+dfsg.1-0ubuntu1+esm7USN-8132-1

Fixed in:1.3.6+dfsg.1-1ubuntu0.1~esm7USN-8132-1

roundcube-pluginsUbuntu

Fixed in:1.2~beta+dfsg.1-0ubuntu1+esm7USN-8132-1

Fixed in:1.3.6+dfsg.1-1ubuntu0.1~esm7USN-8132-1

Remediation is compiled from vendor and distribution security advisories. Always confirm against the linked source for your exact version and platform.

CVSS v3 Vector

Exploitability

Attack VectorNetwork

Attack ComplexityHigh

Privileges RequiredLow

User InteractionNone

ScopeUnchanged

Impact

ConfidentialityHigh

IntegrityHigh

AvailabilityHigh

CVSS:3.0/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H

Exploit Intelligence

5.62%probability of exploitation in 30 days

92ndpercentile

High risk: more likely to be exploited than 92% of all known CVEs.

References

Exploit1

blog.ripstech.com

Vendor Advisory1

roundcube.net

Third-Party Advisory1

openwall.com

Other references2

Related Vulnerabilities

Other CWE-284 (Improper Access Control) vulnerabilities, ordered by exploit likelihood. View all

CVE	Severity	CVSS	EPSS	Exploited	Fix
CVE-2023-27350	Critical	9.8	100%	KEV + Ransom	Fix
CVE-2019-1653	High	7.5	100%	KEV	-
CVE-2023-23752	Medium	5.3	100%	KEV	Fix
CVE-2023-29298	High	7.5	100%	KEV	-
CVE-2023-38205	High	7.5	100%	KEV	-
CVE-2024-27348	Critical	9.8	99%	KEV	Fix

Embed a live status badge for CVE-2016-9920

Markdown

[![CVE-2016-9920](https://tridentstack.com/cve/badge/CVE-2016-9920.svg)](https://tridentstack.com/cve/CVE-2016-9920)

HTML

<a href="https://tridentstack.com/cve/CVE-2016-9920"><img src="https://tridentstack.com/cve/badge/CVE-2016-9920.svg" alt="CVE-2016-9920"></a>

Find and fix vulnerabilities across your fleet

TridentStack Control continuously scans your Windows, macOS, and Linux fleet for known vulnerabilities, prioritizes them by severity and active exploitation, and patches them automatically.

Start free

This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2026-05-06.