Vulnerability · Published Dec 17, 2025 · Assigned by AMZN

CVE-2025-14759

Medium 5.3

In plain English

A medium-severity broken cryptography in S3 Encryption Client for .NET from AWS. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.1% (higher than 1% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)5.3Medium

Exploit odds (30 days)0.1%top 98.9% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

Missing cryptographic key commitment in the Amazon S3 Encryption Client for .NET may allow a user with write access to the S3 bucket to introduce a new EDK that decrypts to different plaintext when the encrypted data key is stored in an "instruction file" instead of S3's metadata record. To mitigate this issue, upgrade Amazon S3 Encryption Client for .NET to version 3.2.0 or later.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
NuGet	amazon.extensions.s3.encryption	3.2.0	GHSA-4v42-65r3-3gjx

Affected products (as reported)

Vendor	Product	Versions
AWS	S3 Encryption Client for .NET	see references

Weakness: CWE-327 · Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:H/A:N

References

https://aws.amazon.com/security/security-bulletins/AWS-2025-032/ vendor-advisory
https://github.com/aws/amazon-s3-encryption-client-dotnet/security/advisories/GHSA-4v42-65r3-3gjx third-party-advisory
https://github.com/aws/amazon-s3-encryption-client-dotnet/releases/tag/release_2025-12-17 patch