CVE-2026-77358
Received
Received - Intake
Use-After-Free in cpp-httplib TLS WebSocket Client
Vulnerability report for CVE-2026-77358, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-08-28
Last updated on: 2026-08-28
Assigner: GitHub, Inc.
Description
Description
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.
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| yhirose | cpp-httplib | to 0.50.1 (exc) |
| yhirose | cpp-httplib | 0.50.1 |
| cpp-httplib | cpp-httplib | From 0.33.0 (inc) to 0.50.0 (inc) |
| cpp-httplib | cpp-httplib | 0.50.1 |
Helpful Resources
Exploitability
CWE
KEV
| CWE ID | Description |
|---|---|
| CWE-416 | The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer. |
