CVE-2026-10536

A use-after-free vulnerability exists in libcurl when an application configures an HTTP/2 stream-dependency tree via `CURLOPT_STREAM_DEPENDS` or `CURLOPT_STREAM_DEPENDS_E`, subsequently invokes `curl_easy_reset()`, and finally terminates the handle with `curl_easy_cleanup()`. During this final cleanup phase, libcurl attempts to access and modify an internal structure that was already freed during the reset operation.

CVSS v3 9.8 CRITICAL

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://curl.se/docs/CVE-2026-10536.html	Patch Vendor Advisory
https://curl.se/docs/CVE-2026-10536.json	Vendor Advisory
https://hackerone.com/reports/3751697	Exploit Issue Tracking Third Party Advisory
https://hackerone.com/reports/3751697	Exploit Issue Tracking Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:haxx:curl:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-07-03 07:16

Updated : 2026-09-15 07:16

NVD link : CVE-2026-10536

Mitre link : CVE-2026-10536

CVE.ORG link : CVE-2026-10536

JSON object : View

Products Affected

haxx

curl

CWE

CWE-416

Use After Free

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