NULL Pointer Dereference Affecting h2o/h2o 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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- published19 Jul 2026
- disclosed17 Jul 2026
- creditNiklas Oberender
Introduced: 17 Jul 2026
CVE-2026-44452 (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 NULL Pointer Dereference in the ClientHello message handling when receiving a zero-length SNI extension. An attacker can cause a segmentation violation and disrupt service availability by sending a specially crafted TLS or QUIC handshake containing a zero-length SNI extension.