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2 vulnerabilities found for AWS Encryption SDK for Python by AWS

CVE-2026-6550 (GCVE-0-2026-6550)

Vulnerability from nvd – Published: 2026-04-20 19:20 – Updated: 2026-04-20 19:44
VLAI
Title
Key commitment policy bypass via shared key cache in AWS Encryption SDK for Python
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.
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
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
  • CWE-757 - Selection of Less-Secure algorithm during negotiation ('algorithm downgrade')
Assigner
References
Impacted products
Vendor Product Version
AWS AWS Encryption SDK for Python Affected: 2 , ≤ 2.5.1 (custom)
Affected: 3 , ≤ 3.3.0 (custom)
Affected: 4 , ≤ 4.0.4 (custom)
Create a notification for this product.
Credits
1seal.org
Show details on NVD website
To clipboard 

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CVE-2026-6550 (GCVE-0-2026-6550)

Vulnerability from cvelistv5 – Published: 2026-04-20 19:20 – Updated: 2026-04-20 19:44
VLAI
Title
Key commitment policy bypass via shared key cache in AWS Encryption SDK for Python
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.
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
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
  • CWE-757 - Selection of Less-Secure algorithm during negotiation ('algorithm downgrade')
Assigner
References
Impacted products
Vendor Product Version
AWS AWS Encryption SDK for Python Affected: 2 , ≤ 2.5.1 (custom)
Affected: 3 , ≤ 3.3.0 (custom)
Affected: 4 , ≤ 4.0.4 (custom)
Create a notification for this product.
Credits
1seal.org
Show details on NVD website
To clipboard 

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