How severe is GHSA-xmrv-pmrh-hhx2?

GHSA-xmrv-pmrh-hhx2 has a CVSS score of 5.9/10, rated MEDIUM. Review your exposure and patch according to your risk tolerance.

How do I fix GHSA-xmrv-pmrh-hhx2?

Update github.com/aws/aws-sdk-go-v2/aws/protocol/eventstream to 1.7.8 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-xmrv-pmrh-hhx2 is resolved across your whole dependency graph.

How do I detect GHSA-xmrv-pmrh-hhx2 in my Go dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/aws/aws-sdk-go-v2/aws/protocol/eventstream, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate GHSA-xmrv-pmrh-hhx2 if there is no patch (or I can't update yet)?

If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

Is GHSA-xmrv-pmrh-hhx2 actively exploited in the wild?

No public exploit code has been indexed for GHSA-xmrv-pmrh-hhx2 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for GHSA-xmrv-pmrh-hhx2?

GHSA-xmrv-pmrh-hhx2 has an EPSS (Exploit Prediction Scoring System) score of 0.3%, placing it in the 23th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is GHSA-xmrv-pmrh-hhx2?

GHSA-xmrv-pmrh-hhx2 is classified as CWE-248 (CWE-248). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was GHSA-xmrv-pmrh-hhx2 published, and has it been updated?

GHSA-xmrv-pmrh-hhx2 was published on April 8, 2026 and was last updated on September 12, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

🐹

🐹 Go

Not in CISA KEV

MEDIUM severity

Denial of Service due to Panic in AWS SDK for Go v2 SDK EventStream DecoderGHSA-xmrv-pmrh-hhx2

MEDIUM

GHSA-xmrv-pmrh-hhx2 is a medium-severity (CVSS 5.9) CWE-248 vulnerability in github.com/aws/aws-sdk-go-v2/aws/protocol/eventstream. A fix is available for github.com/aws/aws-sdk-go-v2/aws/protocol/eventstream — see the affected versions and patch details below.

Also known asCVE-2026-89090GO-2026-5764

Published

Apr 8, 2026

Updated

Sep 12, 2026

Affected

12 pkgs

Patched

12 / 12

Exploits

None indexed

Exploitation data as of Nov 7, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

No confirmed exploitation observed yet

CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.

Exploitation and automatability from CISA’s SSVC triage for GHSA-xmrv-pmrh-hhx2.

EPSS Exploitation Probability

via FIRST.org ↗

0.3%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs23th percentile — riskier than 23% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

How urgent is this, really

Where this sits among everything scored

Real-World Exposure

12 pkgs affected

🐹github.com/aws/aws-sdk-go-v2/aws/protocol/eventstream🐹github.com/aws/aws-sdk-go-v2/service/bedrockagentcore🐹github.com/aws/aws-sdk-go-v2/service/bedrockagentruntime🐹github.com/aws/aws-sdk-go-v2/service/bedrockruntime🐹github.com/aws/aws-sdk-go-v2/service/cloudwatchlogs🐹github.com/aws/aws-sdk-go-v2/service/iotsitewise🐹github.com/aws/aws-sdk-go-v2/service/kinesis🐹github.com/aws/aws-sdk-go-v2/service/lambda+4 more

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.

Description

CVSSv3.1 Rating: [Medium] CVSSv3.1 Score: [5.9] CVSSv3.1 Vector String: [CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H]

Summary and Impact

An issue exists in the the EventStream header decoder in AWS SDK for Go v2 in versions predating 2026-03-23. An actor can send a malformed EventStream response frame containing a crafted header value type byte outside the valid range, which can cause the host process to terminate.

Impacted versions: < 2026-03-23

Patches

This issue has been addressed in versions 2026-03-23 and above. We recommend upgrading to the latest version and ensuring any forked or derivative code is patched to incorporate the new fixes.

Workarounds

Not Applicable

References

If you have any questions or comments about this advisory, we ask that you contact [AWS/Amazon] Security via our vulnerability reporting page or directly via email to [email protected]. Please do not create a public GitHub issue.

Affected Packages

12 total 12 fixed

Ecosystem	Package	Vulnerable range	Fix
🐹Go	`github.com/aws/aws-sdk-go-v2/aws/protocol/eventstream`	all versions	1.7.8`go get github.com/aws/aws-sdk-go-v2/aws/protocol/eventstream@v1.7.8`
🐹Go	`github.com/aws/aws-sdk-go-v2/service/bedrockagentcore`	all versions	1.15.2`go get github.com/aws/aws-sdk-go-v2/service/bedrockagentcore@v1.15.2`
🐹Go	`github.com/aws/aws-sdk-go-v2/service/bedrockagentruntime`	all versions	1.51.8`go get github.com/aws/aws-sdk-go-v2/service/bedrockagentruntime@v1.51.8`
🐹Go	`github.com/aws/aws-sdk-go-v2/service/bedrockruntime`	all versions	1.50.4`go get github.com/aws/aws-sdk-go-v2/service/bedrockruntime@v1.50.4`
🐹Go	`github.com/aws/aws-sdk-go-v2/service/cloudwatchlogs`	all versions	1.65.0`go get github.com/aws/aws-sdk-go-v2/service/cloudwatchlogs@v1.65.0`
🐹Go	`github.com/aws/aws-sdk-go-v2/service/iotsitewise`	all versions	1.52.19`go get github.com/aws/aws-sdk-go-v2/service/iotsitewise@v1.52.19`

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/aws/aws-sdk-go-v2/aws/protocol/eventstream, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update github.com/aws/aws-sdk-go-v2/aws/protocol/eventstream to 1.7.8 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-xmrv-pmrh-hhx2 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

Fixing This On Your OS

If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.

Red HatModerate

A flaw in AWS SDK for Go v2 can cause an application to terminate when it processes an attacker-controlled EventStream response with a crafted header.

Workaround published by Red Hat

Upgrade affected AWS SDK for Go v2 modules to the fixed releases published after 2026-03-23. There is no documented workaround.

Source: Red Hat security advisory for GHSA-xmrv-pmrh-hhx2 (CC BY 4.0)

Product	Fixed in	Advisory
Red Hat OpenShift AI 3.4	`rhai/base-image-neuron-rhel9:1793042008`	RHSA-2026:91248
Red Hat OpenShift AI 3.5	`rhai/base-image-neuron-rhel9:1793042008`	RHSA-2026:91249

Frequently Asked Questions

**CVSSv3.1 Rating**: [Medium] **CVSSv3.1 Score**: [5.9] **CVSSv3.1 Vector String**: [CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H] ## Summary and Impact An issue exists in the the EventStream header decoder in AWS SDK for Go v2 in versions predating [2026-03-23](https://github.com/aws/aws-sdk-go-v2/releases/tag/release-2026-03-23). An actor can send a malformed EventStream response frame containing a crafted header value type byte outside the valid range, which can cause the host process to terminate. Impacted versions: < [2026-03-23](https://github.com/aws/aws-sdk-go-v2/releases/tag/release

O3 Security · Impact-Aware SCA

Is GHSA-xmrv-pmrh-hhx2 in your dependencies?

Find it across Go, including transitive dependencies.

Scan my dependencies How O3 SCA works

CVSS Score

5.9/10CVSS v3 base

Vector breakdown

Attack Vector

Network

Attack Complexity

High

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

High

Raw vector

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

CWE Classification

CWE-248CWE-248

Weaponization

No Nuclei template, Metasploit module or public proof-of-concept found.

Timeline

Disclosed

Apr 8, 2026

Last updated

Sep 12, 2026

Identifiers

GHSA-xmrv-pmrh-hhx2

GO-2026-5764

References

Webgithub.com · GHSA xmrv pmrh hhx2 Webgithub.com · release 2026 03 23 Packagegithub.com · aws sdk go v2

Related vulnerabilities

This CVE is medium severity; 8 of 8 other CVEs with CWE-248 are rated as high or higher (top: high).

CVE-2026-119188CVE-2026-87029CVE-2026-110816CVE-2026-116589CVE-2026-109855CVE-2026-87018CVE-2026-111181CVE-2026-113872Browse all CWE-248

Provenance

Sources

OSV.devNVDFIRST.org (EPSS)

Last verifiedSep 12, 2026