Back to Feed
VulnerabilitiesSep 24, 2026

Hackers now exploit critical Roundcube flaw in code injection attacks

Hackers exploit critical Roundcube flaw CVE-2026-48842 in code injection attacks.

A critical vulnerability in Roundcube Webmail, patched in May as CVE-2026-48842, is now being actively exploited by hackers. This pre-authenticated SQL injection flaw allows attackers to bypass authentication, execute malicious database commands, and steal data. The Canadian Centre for Cyber Security has warned administrators to update their servers or disable the affected virtuser_query plugin.

AI summary of the linked source. Not reviewed by an editor. How this works

Vendor Watch

Run Roundcube Webmail?

Get an email when a new story names Roundcube Webmail, usually within the hour.

Free. Your list stays private and never appears in a subject line. One click stops it. How Vendor Watch worksPrivacy

The lesson from this incident

Full lesson

A pre-authenticated SQL injection vulnerability in Roundcube Webmail (CVE-2026-48842) is being actively exploited despite a patch being available since May, highlighting the persistent danger of delayed patch adoption. Because the flaw requires no prior authentication, attackers can bypass login controls entirely, execute arbitrary database commands, and exfiltrate sensitive data at scale. The fact that exploitation is now widespread indicates that many administrators failed to apply the patch within an acceptable risk window. This case underscores that unpatched internet-facing applications — especially email platforms handling sensitive communications — represent a high-priority attack surface that adversaries actively monitor for newly disclosed vulnerabilities.

What helps against this

How we list vendors

Indicators of Compromise

Extracted by AI from the linked source. Not reviewed by an editor. How this works

  • cve — CVE-2026-48842
  • cve — CVE-2023-5631
  • cve — CVE-2020-35730
  • cve — CVE-2020-12641
  • cve — CVE-2021-44026
  • cve — CVE-2025-49113
  • cve — CVE-2025-68461

Entities

Roundcube Webmail (product)Winter Vivern (threat_actor)APT28 (threat_actor)cPanel (technology)