AWS aws-smithy-json up to 0.62.6 Unknown-Key Skip Path recursion

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.1$0-$5k1.27+

Summaryinfo

A vulnerability was found in AWS aws-smithy-json up to 0.62.6. It has been rated as problematic. This affects an unknown function of the component Unknown-Key Skip Path. Performing a manipulation results in recursion. This vulnerability is cataloged as CVE-2026-18140. It is possible to initiate the attack remotely. There is no exploit available.

Detailsinfo

A vulnerability was found in AWS aws-smithy-json up to 0.62.6. It has been classified as problematic. This affects an unknown function of the component Unknown-Key Skip Path. The manipulation with an unknown input leads to a recursion vulnerability. CWE is classifying the issue as CWE-674. The product does not properly control the amount of recursion that takes place, consuming excessive resources, such as allocated memory or the program stack. This is going to have an impact on availability. The summary by CVE is:

Uncontrolled recursion in the unknown-key skip path of the aws-smithy-json runtime crate before 0.62.7, which the smithy-rs code generator invokes from every generated struct deserializer, might allow remote unauthenticated users to cause a denial of service (process abort via stack exhaustion) via a single small HTTP request containing deeply nested JSON to a smithy-rs generated server. To remediate this issue, users should upgrade to aws-smithy-json 0.62.7 or later and rebuild.

The advisory is shared at crates.io. This vulnerability is uniquely identified as CVE-2026-18140 since 07/28/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. Neither technical details nor an exploit are publicly available. MITRE ATT&CK project uses the attack technique T1499 for this issue.

Upgrading to version 0.62.7 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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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Recursion
CWE: CWE-674 / CWE-404
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
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-json 0.62.7

Timelineinfo

07/28/2026 CVE reserved
07/30/2026 +2 days Advisory disclosed
07/30/2026 +0 days VulDB entry created
07/30/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: crates.io
Status: Confirmed

CVE: CVE-2026-18140 (🔒)
GCVE (CVE): GCVE-0-2026-18140
GCVE (VulDB): GCVE-100-384909

Entryinfo

Created: 07/30/2026 21:07
Changes: 07/30/2026 21:07 (54)
Complete: 🔍
Cache ID: 216::103

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