CVE-2026-110310: falha de média gravidade em Amazon.Extensions.S3.Encryption
RSA PKCS#1 v1.5 padding oracle via legacy envelope key format downgrade in Amazon S3 Encryption Client for .NET
Publicada em
Aviso por e-mail quando ela entrar no KEV, ganhar PoC pública ou subir de nota.
13Vexday Risk Score
Sem sinal de exploração. Nenhum artefato público de exploração conhecido até agora.
ssvc Trackcvss 6epss 0.5%
A remote user who can read encrypted objects in the S3 bucket can force a padding downgrade by altering the padding scheme recorded in an object's metadata to legacy PKCS#1 v1.5. Since this padding scheme is susceptible to the well-known Bleichenbacher attack, the user can use a PKCS#1 v1.5 padding oracle to recover the RSA-wrapped envelope key and decrypt the object.
To remediate this issue, we recommend that users upgrade to version 3.2.2 or 4.0.3. The 1.x and 2.x lines will not be patched, users of those lines need to migrate to 3.2.2 or 4.0.3.
CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N
Produtos afetados
Amazon · Amazon.Extensions.S3.EncryptionReferências
https://aws.amazon.com/security/security-bulletins/2026-135-aws/https://github.com/aws/amazon-s3-encryption-client-dotnet/security/advisories/GHSA-322w-f6rw-r4fjhttps://www.nuget.org/packages/Amazon.Extensions.S3.Encryption/3.2.2https://www.nuget.org/packages/Amazon.Extensions.S3.Encryption/4.0.3