CVE-2026-89090 (CVSS 5.9)

Description

An unrecovered panic in the event stream header decoder in Amazon AWS SDK for Go v2 before release-2026-03-23 might allow an unauthenticated remote actor to terminate the consuming application process via a crafted event stream response frame containing a header value type outside the valid range. To remediate this issue, users should upgrade to release-2026-03-23 or later, and patch any forked or derivative code.

Is your site exposed to CVE-2026-89090?

Run a free security scan — no signup, results in seconds.

CVSS v3.1 Score

5.9

MEDIUM

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS — Exploit Prediction

0.0031

Probability of exploitation

0.24%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-248 CWE-248

References

Other References

https://aws.amazon.com/security/security-bulletins/2026-110-aws/ https://github.com/aws/aws-sdk-go-v2/releases/tag/release-2026-03-23 https://github.com/aws/aws-sdk-go-v2/security/advisories/GHSA-xmrv-pmrh-hhx2

Frequently Asked Questions

What is CVE-2026-89090? +

An unrecovered panic in the event stream header decoder in Amazon AWS SDK for Go v2 before release-2026-03-23 might allow an unauthenticated remote actor to terminate the consuming application process via a crafted event stream response frame containing a header value type outside the valid range. To remediate this issue, users should upgrade to release-2026-03-23 or later, and patch any forked or derivative code. It has a CVSS v3.1 base score of 5.9 (MEDIUM).

How severe is CVE-2026-89090? +

CVE-2026-89090 has a CVSS v3.1 score of 5.9 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance. The EPSS score is 0.0031, placing it in the 0th percentile for exploitation probability.

How do I check if I'm vulnerable to CVE-2026-89090? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

Related Vulnerabilities

CVE-2025-24883

go-ethereum (geth) is a golang execution layer implementation of the Ethereum protocol. A vulnerable node can be forced to shutdown/crash …

CVE-2025-43855

tRPC allows users to build & consume fully typesafe APIs without schemas or code generation. In versions starting from 11.0.0 …

CVE-2025-48997

Multer is a node.js middleware for handling `multipart/form-data`. A vulnerability that is present starting in version 1.4.4-lts.1 and prior to …

CVE-2025-53365

The MCP Python SDK, called `mcp` on PyPI, is a Python implementation of the Model Context Protocol (MCP). Prior to …

CVE-2025-53366

The MCP Python SDK, called `mcp` on PyPI, is a Python implementation of the Model Context Protocol (MCP). Prior to …

CVE-2025-53620

@builder.io/qwik-city is the meta-framework for Qwik. When a Qwik Server Action QRL is executed it dynamically load the file containing …

CVE-2026-89090