Critical severity · published Sep 6, 2026
CVE-2026-18924
HTTP/2 server push UAF
9.1
CVSS
0.6%
EPSS
No
On KEV
Description
A flaw in libcurl's handling of HTTP/2 Server Push streams, when the parent
handle is set to share connections with other handles, can lead to
use-after-free in the cleanup process.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
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
7.44.0 before 8.14.2; 8.15.0 before 8.16.1; 8.17.0 before 8.20.1; 8.21.0 before 8.22.0; ea7134ac874a66107e54ff93657ac565cf2ec4aa before 90325ff0444cbdff368bda5d26d6405a0bb6ee43; 8.21.0; +34 more · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-18924
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-18924
Patch
https://curl.se/docs/CVE-2026-18924.html
Vendor Advisory
https://curl.se/docs/CVE-2026-18924.json
Exploit
https://hackerone.com/reports/3916059
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