CVE-2026-11352

An issue in curl’s QUIC UDP receive function allows a malicious HTTP/3 server to trigger a remote denial of service against a curl or libcurl client. Because the helper function discards zero-length UDP datagrams before counting them toward the per-call packet budget, a connected QUIC peer can continuously stream empty datagrams to indefinitely stall the client.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://curl.se/docs/CVE-2026-11352.html	Patch Vendor Advisory
https://curl.se/docs/CVE-2026-11352.json	Vendor Advisory
https://hackerone.com/reports/3783438	Exploit Issue Tracking Third Party Advisory
https://hackerone.com/reports/3783438	Exploit Issue Tracking Third Party Advisory

Configurations

Configuration 1 (hide)

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

History

07 Jul 2026, 18:01

Type	Values Removed	Values Added
CPE		cpe:2.3:a:haxx:curl::::::::
First Time		Haxx curl Haxx
References	~~() https://curl.se/docs/CVE-2026-11352.html -~~	() https://curl.se/docs/CVE-2026-11352.html - Patch, Vendor Advisory
References	~~() https://curl.se/docs/CVE-2026-11352.json -~~	() https://curl.se/docs/CVE-2026-11352.json - Vendor Advisory
References	~~() https://hackerone.com/reports/3783438 -~~	() https://hackerone.com/reports/3783438 - Exploit, Issue Tracking, Third Party Advisory
CWE		CWE-835

06 Jul 2026, 19:16

Type	Values Removed	Values Added
References	~~() https://hackerone.com/reports/3783438 -~~	() https://hackerone.com/reports/3783438 -
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 7.5

03 Jul 2026, 07:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-03 07:16

Updated : 2026-07-07 18:01

NVD link : CVE-2026-11352

Mitre link : CVE-2026-11352

CVE.ORG link : CVE-2026-11352

JSON object : View

Products Affected

haxx

curl

CWE

CWE-835

Loop with Unreachable Exit Condition ('Infinite Loop')

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