Heap-based Buffer Overflow Affecting libssh2 package, versions [0,]
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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- published25 Jul 2026
- disclosed24 Jul 2026
- creditUnknown
Introduced: 24 Jul 2026
NewCVE-2026-66035 (opens in a new tab)How to fix?
A fix was pushed into the master branch but not yet published.
Overview
Affected versions of this package are vulnerable to Heap-based Buffer Overflow in the fullpacket function during Encrypt-then-MAC cipher negotiation. An attacker can corrupt heap metadata and potentially achieve arbitrary code execution or cause a denial of service by sending a specially crafted packet with a packet_length smaller than the cipher's block size, leading to a heap buffer overflow during the session handshake before authentication.