CVE-2026-57511
MediumCVSS 5.4Exploitation Probability (EPSS)
Low risk15th percentile - higher than 15% of all known CVEs
Summary
SuperPlane before 0.30.0 contains an SMTP header injection vulnerability allowing unauthenticated attackers to inject arbitrary SMTP headers by including CRLF sequences in the event payload title field delivered via webhook. Attackers can manipulate the unsanitized title field passed to the SMTP DATA command to add Bcc recipients for content exfiltration, forge the From address to bypass SPF and DKIM checks, or inject Content-Type and MIME boundary headers to corrupt message bodies for phishing.
Risk Assessment
An unauthenticated attacker can send forged emails, steal content, or conduct phishing attacks, potentially causing reputational and financial damage to the organization.
Recommendation
Upgrade to version 0.30.0 or later, which contains the fix.
Other vulnerabilities in SuperPlane
Original NVD description (English source)
SuperPlane before 0.30.0 contains an SMTP header injection vulnerability that allows unauthenticated attackers to inject arbitrary SMTP headers by including CRLF sequences in the event payload title field delivered via webhook. Attackers can manipulate the unsanitized title field passed to the SMTP DATA command to add Bcc recipients for content exfiltration, forge the From address to bypass SPF and DKIM checks, or inject Content-Type and MIME boundary headers to corrupt message bodies for phishing.

