CVE-2026-18140 - Uncontrolled recursion in the aws-smithy-json unknown-key skip path allows unauthenticated remote denial of service in smithy-rs generated servers

unknownCVE-2026-18140

Please refer to the article below for the most up-to-date and complete information related to this AWS Security Bulletin.

Details

Source: AWS Security Bulletins (INTL · vendor-psirt · site)
Severity: unknown
Published: 2026-07-31
Exploitation: Not in CISA KEV at last sync

Original advisory: https://aws.amazon.com/security/security-bulletins/rss/2026-067-aws/

Exploitation outlook

EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.

Low exploitation riskCVE-2026-181400.44% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 36% of all scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-18140	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.

highCVE-2026-18140: Uncontrolled recursion in the unknown-key skip path of the aws-smithy-json runtime crate befor…nvd

Recent advisories for - Uncontrolled recursion

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