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)
CWE
- CWE-757 - Selection of Less-Secure algorithm during negotiation ('algorithm downgrade')
Assigner
References
| URL | Tags | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
||||||||||||||
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) |
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Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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