AWS aws-smithy-http-server up to 0.66.4 serve resource consumption

CVSS Meta Temp Score
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CTI Interest Score
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5.1$0-$5k0.00

Summaryinfo

A vulnerability categorized as problematic has been discovered in AWS aws-smithy-http-server up to 0.66.4. This issue affects the function serve. The manipulation results in resource consumption. This vulnerability is reported as CVE-2026-16756. The attack can be launched remotely. No exploit exists.

Detailsinfo

A vulnerability, which was classified as problematic, was found in AWS aws-smithy-http-server up to 0.66.4. Affected is the function serve. The manipulation with an unknown input leads to a resource consumption vulnerability. CWE is classifying the issue as CWE-400. The product does not properly control the allocation and maintenance of a limited resource, thereby enabling an actor to influence the amount of resources consumed, eventually leading to the exhaustion of available resources. This is going to have an impact on availability. CVE summarizes:

Missing connection and header-read timeouts and the absence of a concurrent-connection cap in the default serve() path of Amazon aws-smithy-http-server might allow remote attackers to cause a denial of service by opening many connections and sending partial requests that are never completed, exhausting server sockets and tasks. To mitigate this issue, users should upgrade to aws-smithy-http-server 0.66.5 or later.

The advisory is available at crates.io. This vulnerability is traded as CVE-2026-16756 since 07/23/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. Technical details are known, but there is no available exploit. This vulnerability is assigned to T1499 by the MITRE ATT&CK project.

Upgrading to version 0.66.5 eliminates this vulnerability.

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Productinfo

Vendor

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.3
VulDB Meta Temp Score: 5.1

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Resource consumption
CWE: CWE-400 / CWE-404
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: aws-smithy-http-server 0.66.5

Timelineinfo

07/23/2026 Advisory disclosed
07/23/2026 +0 days CVE reserved
07/23/2026 +0 days VulDB entry created
07/23/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: crates.io
Status: Confirmed

CVE: CVE-2026-16756 (🔒)
GCVE (CVE): GCVE-0-2026-16756
GCVE (VulDB): GCVE-100-382782

Entryinfo

Created: 07/23/2026 21:00
Changes: 07/23/2026 21:00 (54)
Complete: 🔍
Cache ID: 216::103

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