CVE-2020-8911

Aliases:GHSA-f5pg-7wfw-84q9GO-2022-0646
Advisory lineage Upstream: 0 Downstream: 1
Modified
Published: 11 Aug 2020, 19:20
Last modified:04 Aug 2024, 10:12

Vulnerability Summary

Overall Risk (default)
medium
32/100
CVSS Score
5.6 MEDIUM
v3.1 (cve.org)
EPSS Score
0.2% LOW
0% probability 0.00%
KEV
Not listed
Ransomware
No reports
Public exploits
1 found
Dark Web
Not detected

Timeline

11 Aug 2020, 19:20
Published
Vulnerability first disclosed
04 Aug 2024, 10:12
Last Modified
Vulnerability information updated

Description

A padding oracle vulnerability exists in the AWS S3 Crypto SDK for GoLang versions prior to V2. The SDK allows users to encrypt files with AES-CBC without computing a Message Authentication Code (MAC), which then allows an attacker who has write access to the target's S3 bucket and can observe whether or not an endpoint with access to the key can decrypt a file, they can reconstruct the plaintext with (on average) 128*length (plaintext) queries to the endpoint, by exploiting CBC's ability to manipulate the bytes of the next block and PKCS5 padding errors. It is recommended to update your SDK to V2 or later, and re-encrypt your files.

CVSS Metrics

  • v3.1•MEDIUM•Score: 5.6CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:N/A:N
  • v2.0•LOW•Score: 2.1AV:L/AC:L/Au:N/C:P/I:N/A:N

EPSS Trends

Current EPSS score: 0.20%• Percentile: 42%

Techniques & Countermeasures

  • CWE-327•Use of a Broken or Risky Cryptographic Algorithm

    The product uses a broken or risky cryptographic algorithm or protocol.

Affected Systems

  • amazon•aws_s3_crypto_sdk

    < 2.0

  • github.com/aws•aws-sdk-go

    all | < 1.34.0

  • google llc•aws s3 crypto sdk for golang

    ≥ stable, ≤ V1

References (10)