CVE-2026-94450 - Potential denial of service when configured to send Retry packets in s2n-quic
CVE-2026-94450 is a denial of service vulnerability in s2n-quic, a Rust implementation of the QUIC protocol. The flaw involves improper validation of the Destination Connection ID length when a server is configured to send Retry packets. This allows an unauthenticated attacker to shut down a server endpoint with a single crafted UDP datagram. The issue affects s2n-quic versions 1.88.0 and earlier. AWS services are not impacted, and only server endpoints configured to issue Retry packets are vulnerable. The vulnerability is fixed in s2n-quic version 1.89.0. No workaround exists, so upgrading is necessary.
AI Analysis
Technical Summary
The vulnerability CVE-2026-94450 in s2n-quic arises from improper validation of the Destination Connection ID length in Retry packets sent by the server. This flaw permits an unauthenticated user to cause a denial of service by shutting down a server endpoint via a single crafted UDP datagram. The affected versions are s2n-quic 1.88.0 and earlier. AWS services themselves are not affected, and only server endpoints specifically configured to send Retry packets are vulnerable. The issue has been resolved in version 1.89.0 of s2n-quic.
Potential Impact
An unauthenticated attacker can cause a denial of service condition by shutting down a vulnerable s2n-quic server endpoint with a single crafted UDP packet. This disrupts availability of the affected server endpoint. No AWS cloud services are impacted, limiting the scope to self-hosted or third-party deployments of s2n-quic configured to send Retry packets.
Mitigation Recommendations
The vulnerability is fixed in s2n-quic version 1.89.0. Users should upgrade to this version or later to remediate the issue. There is no workaround available. AWS customers using AWS services do not need to take any action as those services are not affected.
CVE-2026-94450 - Potential denial of service when configured to send Retry packets in s2n-quic
Description
CVE-2026-94450 is a denial of service vulnerability in s2n-quic, a Rust implementation of the QUIC protocol. The flaw involves improper validation of the Destination Connection ID length when a server is configured to send Retry packets. This allows an unauthenticated attacker to shut down a server endpoint with a single crafted UDP datagram. The issue affects s2n-quic versions 1.88.0 and earlier. AWS services are not impacted, and only server endpoints configured to issue Retry packets are vulnerable. The vulnerability is fixed in s2n-quic version 1.89.0. No workaround exists, so upgrading is necessary.
Affected software
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The vulnerability CVE-2026-94450 in s2n-quic arises from improper validation of the Destination Connection ID length in Retry packets sent by the server. This flaw permits an unauthenticated user to cause a denial of service by shutting down a server endpoint via a single crafted UDP datagram. The affected versions are s2n-quic 1.88.0 and earlier. AWS services themselves are not affected, and only server endpoints specifically configured to send Retry packets are vulnerable. The issue has been resolved in version 1.89.0 of s2n-quic.
Potential Impact
An unauthenticated attacker can cause a denial of service condition by shutting down a vulnerable s2n-quic server endpoint with a single crafted UDP packet. This disrupts availability of the affected server endpoint. No AWS cloud services are impacted, limiting the scope to self-hosted or third-party deployments of s2n-quic configured to send Retry packets.
Mitigation Recommendations
The vulnerability is fixed in s2n-quic version 1.89.0. Users should upgrade to this version or later to remediate the issue. There is no workaround available. AWS customers using AWS services do not need to take any action as those services are not affected.
Technical Details
- Classification
- {"confidence":0.88,"severitySource":"heuristic","classifier":"rss-v2"}
- Article Source
- {"url":"https://aws.amazon.com/security/security-bulletins/rss/2026-116-aws/","fetched":true,"fetchedAt":"2026-09-22T20:15:59.668Z","wordCount":182}
Threat ID: 6ab2e1fff7a7c54106b5f7d2
Added to database: 09/22/2026, 20:15:59 UTC
Last enriched: 09/22/2026, 20:16:08 UTC
Last updated: 09/22/2026, 20:16:08 UTC
Views: 1
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