CVE-2026-12043 Affecting mount-s3 package, versions <0:1.23.0-1.amzn2023
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Test your applications- Snyk IDSNYK-AMZN2023-MOUNTS3-21159042
- published17 Oct 2026
- disclosed12 Jun 2026
Introduced: 12 Jun 2026
CVE-2026-12043 (opens in a new tab)How to fix?
Upgrade Amazon-Linux:2023 mount-s3 to version 0:1.23.0-1.amzn2023 or higher.
This issue was patched in ALAS2023-2026-3233.
NVD Description
Note: Versions mentioned in the description apply only to the upstream mount-s3 package and not the mount-s3 package as distributed by Amazon-Linux.
See How to fix? for Amazon-Linux:2023 relevant fixed versions and status.
Improper handling of HPACK dynamic table size updates in the AWS Common Runtime aws-c-http library might allow a remote threat actor operating a server to cause memory corruption on a connecting client application, potentially leading to arbitrary code execution, via a crafted sequence of HTTP/2 HEADERS frames.
To remediate this issue, users should upgrade to aws-c-http version 0.11.0.