Vulnerability · Published Aug 12, 2026 · Assigned by AMZN
CVE-2026-19643Out-of-bounds read in the Base64 decoder in Amazon aws-sdk-cpp on signed-char platforms
Medium 5.3
In plain English
A medium-severity out-of-bounds read in aws-sdk-cpp from AWS. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.6% (higher than 47% of all known vulnerabilities).
Severity (CVSS 3.1)5.3Medium
Exploit odds (30 days)0.6%top 52.9% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official description
An out-of-bounds read issue in the Base64 decoder in Amazon aws-sdk-cpp before 1.11.862, on some platforms, might allow a remote authenticated user to crash an application that processes crafted Base64-encoded input. To remediate this issue, users should upgrade to version 1.11.862.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| AWS | aws-sdk-cpp | 0 – through 1.11.861 |
Weakness: CWE-125 · Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
References
- https://github.com/aws/aws-sdk-cpp/releases/tag/1.11.862 release-notes, patch
- https://aws.amazon.com/security/security-bulletins/2026-080-aws/ vendor-advisory
- https://github.com/aws/aws-sdk-cpp/security/advisories/GHSA-mxm9-xpf9-x66x release-notes