CyberSecBulletin
CVE-2026-114720NVD status: Analyzed

Webmail: Improper Neutralization of CRLF Sequences

CVE-2026-114720 is a high-severity improper neutralization of CRLF sequences vulnerability in Webmail from Roundcube, with a CVSS 3.1 base score of 7.1 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 0.79% chance of exploitation within 30 days, higher than 57% of scored 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
UnchangedImpact stays within the vulnerable component.
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:U/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 an IMAP command injection vulnerability. A remote authenticated attacker can exploit this via CRLF sequences injected into the _flag parameter of the mail/mark action to execute arbitrary IMAP commands. Upstream fixed this in the commit “Fix IMAP command injection via CRLF in `_flag` parameter of mail/mark action”, which rejects flags containing control, whitespace and IMAP-special characters.

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

The underlying weakness: Improper Neutralization of CRLF Sequences

The product uses CRLF (carriage return line feeds) as a special element, e.g. to separate lines or records, but it does not neutralize or incorrectly neutralizes CRLF sequences from inputs.

How developers prevent this class of flaw

  • Appropriately filter or quote CRLF sequences in user-controlled input.

More Improper Neutralization of CRLF Sequences vulnerabilities (CWE-93)

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 Neutralization of CRLF Sequences vulnerabilities

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