CVE-2026-66032
libssh2 double-free in sftp_open allows heap corruption and potential RCE for SFTP clients
Is CVE-2026-66032 being exploited?
Not confirmed. CVE-2026-66032 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 0.45% probability of exploitation in the next 30 days.
How severe is CVE-2026-66032?
CVE-2026-66032 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-2026-66032?
Yes. A fix has been recorded for CVE-2026-66032. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-66032 affect?
CVE-2026-66032 affects libssh2 <= 1.11.1, SFTP clients embedding libssh2, Applications and devices using libssh2 for SFTP. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-66032?
Upgrade libssh2 to the commit-fixed version (5e47761) and avoid untrusted SFTP servers
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Malicious SSH server can trigger a double-free during SFTP open, causing heap corruption/tcache dup and likely remote code execution on authenticated clients (glibc).
Patch when possible
- affected<= 1.11.1
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.