Critical severity · published Jul 3, 2026
CVE-2026-10536
HTTP/2 stream-dependency tree UAF
9.8
CVSS
0.6%
EPSS
No
On KEV
Description
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 vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.6% · higher than 48% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CU
curl · curl
7.88.0 before 8.14.2; 8.15.0 before 8.16.1; 8.17.0 before 8.20.1; 71b7e0161032927cdfb4e75ea40f65b8898b3956 before bfbff7852f050232edd3e5ca5c6bf2021c340f5a; 8.20.0; 8.19.0; +31 more · source: vendor, NVD
Affected product
CU
curl
curl
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