CVE-2026-16756 - Allocation of resources without limits in the default aws-smithy-http-server serve() path allows unauthenticated Slowloris denial of service
CVE-2026-16756 is a vulnerability in the aws-smithy-http-server component (version 0.66.4 and earlier) where resource allocation without limits in the default serve() path allows an unauthenticated attacker to perform a Slowloris denial of service attack. This vulnerability affects the AWS SDK for Rust and custom services using Smithy-RS. The issue has been fixed in version 0.66.5. No workaround exists other than upgrading to the patched version.
AI Analysis
Technical Summary
The vulnerability CVE-2026-16756 affects aws-smithy-http-server versions up to 0.66.4. It arises from the allocation of resources without limits in the default serve() path, enabling unauthenticated attackers to launch Slowloris-style denial of service attacks. Smithy-RS is a Rust framework used to generate HTTP clients and servers for AWS SDK for Rust and custom services. The issue has been addressed in version 0.66.5, which imposes resource limits to mitigate this attack vector.
Potential Impact
An unauthenticated attacker can exploit this vulnerability to cause a denial of service by exhausting server resources through a Slowloris attack. This can disrupt availability of services relying on aws-smithy-http-server versions 0.66.4 and earlier. There is no indication of remote code execution or data compromise from this vulnerability.
Mitigation Recommendations
Upgrade aws-smithy-http-server to version 0.66.5 or later, which contains the official fix for this vulnerability. There are no workarounds other than applying this update. Ensure any forked or derivative code is also patched accordingly.
CVE-2026-16756 - Allocation of resources without limits in the default aws-smithy-http-server serve() path allows unauthenticated Slowloris denial of service
Description
CVE-2026-16756 is a vulnerability in the aws-smithy-http-server component (version 0.66.4 and earlier) where resource allocation without limits in the default serve() path allows an unauthenticated attacker to perform a Slowloris denial of service attack. This vulnerability affects the AWS SDK for Rust and custom services using Smithy-RS. The issue has been fixed in version 0.66.5. No workaround exists other than upgrading to the patched version.
Affected software
pkg:cargo/aws-smithy-http-serverRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The vulnerability CVE-2026-16756 affects aws-smithy-http-server versions up to 0.66.4. It arises from the allocation of resources without limits in the default serve() path, enabling unauthenticated attackers to launch Slowloris-style denial of service attacks. Smithy-RS is a Rust framework used to generate HTTP clients and servers for AWS SDK for Rust and custom services. The issue has been addressed in version 0.66.5, which imposes resource limits to mitigate this attack vector.
Potential Impact
An unauthenticated attacker can exploit this vulnerability to cause a denial of service by exhausting server resources through a Slowloris attack. This can disrupt availability of services relying on aws-smithy-http-server versions 0.66.4 and earlier. There is no indication of remote code execution or data compromise from this vulnerability.
Mitigation Recommendations
Upgrade aws-smithy-http-server to version 0.66.5 or later, which contains the official fix for this vulnerability. There are no workarounds other than applying this update. Ensure any forked or derivative code is also patched accordingly.
Technical Details
- Article Source
- {"url":"https://aws.amazon.com/security/security-bulletins/rss/2026-064-aws/","fetched":true,"fetchedAt":"2026-07-23T18:47:37.780Z","wordCount":171}
Threat ID: 6a6261c99c2644c7f888dc65
Added to database: 07/23/2026, 18:47:37 UTC
Last enriched: 07/23/2026, 18:47:47 UTC
Last updated: 07/23/2026, 19:31:51 UTC
Views: 7
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