Denial of Service Vulnerability in Amazon.IonDotnet by Amazon
CVE-2025-3857

8.7HIGH

Key Information:

Vendor

Amazon

Status
Amazon Ion Dotnet
Vendor
CVE Published:
21 April 2025

What is CVE-2025-3857?

The vulnerability arises in Amazon.IonDotnet's RawBinaryReader class, which lacks proper checks on the byte count when reading binary Ion data from the underlying stream. In cases where the Ion data is malformed or truncated, this oversight can lead to an infinite loop condition. As a result, the affected system may experience a denial of service. Users are advised to upgrade to Amazon.IonDotnet version 1.3.1 and ensure that any forked or derivative versions are also updated to mitigate this issue.

Affected Version(s)

Amazon Ion Dotnet 0 < 1.3.1

References

https://aws.amazon.com/security/security-bulletins/AWS-20...
vendor-advisory
https://github.com/amazon-ion/ion-dotnet/security/advisor...
third-party-advisory

CVSS V4

Score:
8.7
Severity:
HIGH
Confidentiality:
None
Integrity:
None
Availability:
High
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • Vulnerability published

  • Vulnerability Reserved

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CVE-2025-3857 : Denial of Service Vulnerability in Amazon.IonDotnet by Amazon