CVE-2026-63090
Authenticated heap overflow in ProFTPD mod_sftp allows remote code execution.
Is CVE-2026-63090 being exploited?
Not confirmed. CVE-2026-63090 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.93% probability of exploitation in the next 30 days.
How severe is CVE-2026-63090?
CVE-2026-63090 is rated High with a CVSS score of 8.7. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-63090?
Yes. A fix has been recorded for CVE-2026-63090. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-63090 affect?
CVE-2026-63090 affects ProFTPD (mod_sftp) versions before 1.3.9c, ProFTPD (mod_sftp) versions before 1.3.10rc3. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-63090?
Upgrade to ProFTPD 1.3.9c/1.3.10rc3+ or disable mod_sftp immediately
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Authenticated low‑priv attacker can send oversized SFTP fragments to trigger a heap overflow and achieve arbitrary code execution (invoke system()).
Immediate action required
- affected< 1.3.9c
- affected>= 1.3.10rc1 and < 1.3.10rc3
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.