CyberSecBulletin
CVE-2026-114716NVD status: Analyzed

Webmail: Improper Control of Resource Identifiers

Published Updated By the CyberSecBulletin desk

CVE-2026-114716 is a high-severity improper control of resource identifiers vulnerability in Webmail from Roundcube, with a CVSS 3.1 base score of 8.5 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, without any action from a user. The record lists versions 1.6.20, 1.7.5 as the first without the flaw, so updating Webmail to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.39% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update Webmail to 1.6.20 or 1.7.5, whichever matches your release line, or a later version.

Affected products and versions

VendorProductAffected versionsFixed in
RoundcubeWebmail1.6.0 up to, but not including, 1.6.20; 1.7.0 up to, but not including, 1.7.51.6.20, 1.7.5

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
LowA basic user account is enough.
User interaction
NoneNo action by a victim is required.
Scope
ChangedThe attack can reach beyond the vulnerable component into other systems.
Confidentiality
LowSome restricted data can be read.
Integrity
HighData or code can be modified at will.
Availability
NoneAvailability is not affected.

Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:H/A:N. Scored by CNA (mitre.org).

Official description

Roundcube Webmail before 1.6.20 and 1.7.x before 1.7.5 is affected by a mail header injection vulnerability. rcmail_sendmail::extract_inline_images() used the media type taken from an inline image data URI without validating it, so a remote authenticated attacker could inject arbitrary MIME part headers into the outgoing message by placing CRLF sequences in that media type. Upstream fixed this in the commit “Fix mail header injection via media type in an inline image data URI”, which validates the media type with rcube_mime::is_mimetype_valid().

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Improper Control of Resource Identifiers

The product receives input from an upstream component, but it does not restrict or incorrectly restricts the input before it is used as an identifier for a resource that may be outside the intended control sphere.

More Improper Control of Resource Identifiers vulnerabilities (CWE-99)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: partial).
  3. Record last changed materially (score, affected products, status or references).

References

Third-party and government advisories

Other vulnerabilities in Webmail

All Webmail vulnerabilities

Recent Improper Control of Resource Identifiers vulnerabilities

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