CVE-2026-66032: libssh2 Double-Free Heap Corruption via sftp_open()
CSIRTS triage
- What
- A double-free heap corruption vulnerability exists in the sftp_open() function.
- Who is affected
- Deployments using libssh2 are affected.
- Urgency
- Remediation is urgent due to high severity (CVSS 8.8) and potential for exploitation.
- Action
- Update to the patched version of libssh2.
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Details
Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-66032
Exploitation outlook
EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.
- Low exploitation riskCVE-2026-660320.29% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 21% of all scored CVEs.
Referenced CVEs
| CVE | CSIRTS overview | External |
|---|---|---|
| CVE-2026-66032 | coverage & exploitation status | NVD · CVE.org |
Same CVEs, other sources
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