CVE-2016-9920

VendorroundcubeProductwebmailDiscoveredDec 8, 2016UpdatedMay 6, 2026

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.

View graph Watch Export

CVSS v3.1

7.5 HIGH

EPSS

5.60%

probability of exploitation in 30 days

CISA KEV

Not listed

no confirmed exploitation reported

News coverage

sources referencing this CVE

Related IOCs

seen in the same coverage

EPSS Trend

Aug 16, 2026 → Sep 23, 2026

▼ 0.02pp

5.62% → 5.60% over 11 tracked changes

CVSS v3.1 Detail

Attack VectorNETWORK

Attack ComplexityHIGH

Privileges RequiredLOW

User InteractionNONE

ScopeUNCHANGED

ConfidentialityHIGH

IntegrityHIGH

AvailabilityHIGH

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

Connections

3 relationships

CWE-284

source

Timeline

disclosure → media coverage

Dec 8, 2016

Disclosure — published as a CVE record. · last revised by NVD May 6, 2026

Mar 30, 2026

ubuntu.com reports: USN-8132-1: Roundcube Webmail vulnerabilities

Public PoC (1)

github.com/t0kx/exploit-CVE-2016-9920

Unverified third-party code — review before executing.