CVE-2026-6550 (GCVE-0-2026-6550)
Vulnerability from cvelistv5
Published
2026-04-20 19:20
Modified
2026-04-20 19:44
Severity ?
4.7 (Medium) - CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:H/A:N
5.7 (Medium) - CVSS:4.0/AV:L/AC:H/AT:P/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N
CWE
  • CWE-757 - Selection of Less-Secure algorithm during negotiation ('algorithm downgrade')
Summary
Cryptographic algorithm downgrade in the caching layer of Amazon AWS Encryption SDK for Python before version 3.3.1 and before version 4.0.5 might allow an authenticated local threat actor to bypass key commitment policy enforcement via a shared key cache, resulting in ciphertext that can be decrypted to multiple different plaintexts. To remediate this issue, users should upgrade to version 3.3.1, 4.0.5 or above.
References
Impacted products
Vendor Product Version
AWS AWS Encryption SDK for Python Version: 2   <
Version: 3   <
Version: 4   <
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