Amazon.IonDotnet is vulnerable to Denial of Service attacks

Not analysed yet

We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.

Severity and exploitation

• CISA KEV Not listed.
• EPSS 0.0043, the 37th percentile, on 5 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

Timeline

1. 31 Oct 2026, 15:22 UTC First seen by agentprime
2. 31 Oct 2026, 15:22 UTC Confirmed by OSV

Sources

• GitHub Advisory Database: GHSA-q5r6-9qwq-g2wj
• OSV: GHSA-q5r6-9qwq-g2wj
• github.com/amazon-ion/ion-dotnet/security/advisories/GHSA-q5r6-9qwq-g2wj
• nvd.nist.gov/vuln/detail/CVE-2025-11573
• github.com/amazon-ion/ion-dotnet/pull/160
• github.com/amazon-ion/ion-dotnet/commit/edaff75fe5abbb71e647bed812c608c0c5e2fbab
• aws.amazon.com/security/security-bulletins/AWS-2025-022
• github.com/amazon-ion/ion-dotnet
• github.com/amazon-ion/ion-dotnet/releases/tag/v1.3.2

Facts on this page come from the GitHub Advisory Database (CC-BY 4.0), OSV and the other sources listed, as published. We don’t reproduce full advisory descriptions, which can contain exploit code.