Double Free Affecting openssl package, versions [3.5.0,]
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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Test your applications- Snyk IDSNYK-CONAN-OPENSSL-19267468
- published26 Aug 2026
- disclosed25 Aug 2026
- creditFuzz0x (ZKSC Institute of Security Research), Feng Xue (ThreatBoon), Emilio Galle
Introduced: 25 Aug 2026
NewCVE-2026-18798 (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 Double Free in QRX handling during channel creation failure. An attacker can trigger heap corruption and terminate the QUIC server process by sending a malformed INITIAL packet that makes port_bind_channel() fail after QRX allocation and validation. When channel binding fails, the same OSSL_QRX object is freed on the port_bind_channel() error path and then freed again by port_default_packet_handler(), causing a denial of service.