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

07 Jul 2026, 18:02

Type	Values Removed	Values Added
References	~~() https://curl.se/docs/CVE-2026-10536.html -~~	() https://curl.se/docs/CVE-2026-10536.html - Patch, Vendor Advisory
References	~~() https://curl.se/docs/CVE-2026-10536.json -~~	() https://curl.se/docs/CVE-2026-10536.json - Vendor Advisory
References	~~() https://hackerone.com/reports/3751697 -~~	() https://hackerone.com/reports/3751697 - Exploit, Issue Tracking, Third Party Advisory
CPE		cpe:2.3:a:haxx:curl::::::::
First Time		Haxx curl Haxx
CWE		CWE-416

06 Jul 2026, 19:16

Type	Values Removed	Values Added
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 9.8
References	~~() https://hackerone.com/reports/3751697 -~~	() https://hackerone.com/reports/3751697 -

03 Jul 2026, 07:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-03 07:16

Updated : 2026-07-07 18:02

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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