CVE-2026-94450

Improper validation of the Destination Connection ID length in s2n-quic 1.88.0 and earlier may allow an unauthenticated remote user to cause a denial of service by shutting down a server endpoint via a single crafted UDP datagram. Only server endpoints specifically configured to send Retry packets are affected. To remediate this issue, users should upgrade to version v1.89.0 or later.

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://aws.amazon.com/security/security-bulletins/2026-116-aws/
https://github.com/aws/s2n-quic/releases/tag/v1.89.0
https://github.com/aws/s2n-quic/security/advisories/GHSA-5rw2-6x5m-v22x

Configurations

No configuration.

History

20 Oct 2026, 19:19

Type	Values Removed	Values Added
CWE		CWE-617

22 Sep 2026, 21:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-22 21:17

Updated : 2026-10-20 19:19

NVD link : CVE-2026-94450

Mitre link : CVE-2026-94450

CVE.ORG link : CVE-2026-94450

JSON object : View

Products Affected

No product.

CWE

CWE-617

Reachable Assertion

CWE-1284

Improper Validation of Specified Quantity in Input

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