8.2
HIGH CVSS 4.0
CVE-2026-77358
cpp-httplib: Use-after-free of TLS session in WebSocketClient::shutdown_and_close()
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.

INFO

Published Date :

Aug. 28, 2026, 12:18 a.m.

Last Modified :

Aug. 28, 2026, 12:18 a.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-77358 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Yhirose cpp-httplib
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 4.0 HIGH [email protected]
Solution
Update cpp-httplib to version 0.50.1 or later to fix a use-after-free vulnerability.
  • Update cpp-httplib to version 0.50.1.
  • Apply the fix to the WebSocket client shutdown logic.
  • Ensure TLS session is managed correctly.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-77358.

URL Resource
https://github.com/yhirose/cpp-httplib/commit/2f986fd5e56e7c5f686d965174516360930f371d
https://github.com/yhirose/cpp-httplib/security/advisories/GHSA-w7p7-f35j-mw7q
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-77358 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-77358 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-77358 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-77358 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Aug. 28, 2026

    Action Type Old Value New Value
    Added 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.
    Added CVSS V4.0 AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
    Added CWE CWE-416
    Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/77xxx/CVE-2026-77358.json">CVE-2026-77358</a>
    Added Reference https://github.com/yhirose/cpp-httplib/commit/2f986fd5e56e7c5f686d965174516360930f371d
    Added Reference https://github.com/yhirose/cpp-httplib/security/advisories/GHSA-w7p7-f35j-mw7q
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.