Use After Free Affecting cpp-httplib package, versions *


Severity

Recommended
low

Based on default assessment until relevant scores are available.

Threat Intelligence

EPSS
0.29% (21st percentile)

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  • Snyk IDSNYK-DEBIAN12-CPPHTTPLIB-19402179
  • published28 Aug 2026
  • disclosed28 Aug 2026

Introduced: 28 Aug 2026

NewCVE-2026-77358  (opens in a new tab)
CWE-416  (opens in a new tab)

How to fix?

There is no fixed version for Debian:12 cpp-httplib.

NVD Description

Note: Versions mentioned in the description apply only to the upstream cpp-httplib package and not the cpp-httplib package as distributed by Debian. See How to fix? for Debian:12 relevant fixed versions and status.

cpp-httplib is a C++ header-only HTTP/HTTPS library. In versions 0.33.0 through 0.50.0, the TLS-enabled WebSocket client frees the TLS session before closing the WebSocket that still uses it, producing a use-after-free. In WebSocketClient::shutdown_and_close the SSL object is freed and the pointer cleared, but the subsequent WebSocket close still sends a close frame through the SSL socket stream, which holds a raw copy of the now-dangling session pointer and reads from and writes to the freed memory. The same freed-then-used ordering is reachable through the client's destructor and its connect path, so ordinary teardown of a secure WebSocket connection triggers the defect. This issue is fixed in version 0.50.1.