GHSA-27f5-xjrr-q9ff — critical GitHub Advisory in npm/@opensearch-project/opensearch

Description

Overview

The OpenSearch Project has sustained a security incident involving an external actor gaining force-push permissions within the project's CI infrastructure to embed malicious packages into four release versions of @opensearch-project/opensearch. Users are instructed to immediately take actions recommended in the Remediation section of this advisory.

Affected Versions

Package: @opensearch-project/opensearch

Version	Published (UTC)	Published (America/New_York)
3.5.3	2026-05-12T00:47:39Z	May 11, 2026, 8:47:39 PM EDT
3.6.2	2026-05-12T00:29:34Z	May 11, 2026, 8:29:34 PM EDT
3.7.0	2026-05-12T00:42:29Z	May 11, 2026, 8:42:29 PM EDT
3.8.0	2026-05-12T00:43:54Z	May 11, 2026, 8:43:54 PM EDT

Remediation

Any computer that has these package versions installed or updated between 00:00 UTC 12 May 2026 (8:00 PM EDT 11 May 2026) and 10:00 UTC 12 May 2026 (6:00 AM EDT 12 May 2026) should be considered fully compromised. Steps should immediately be taken to prevent further compromise.

All secrets and keys stored on that computer should be rotated immediately from an alternate system.
The affected packages should be removed immediately, but as full control of the computer may have been given to an outside entity, there is no guarantee that removing the package will remove all malicious software resulting from installing it.

References

GHSA-g7cv-rxg3-hmpx
https://github.com/TanStack/router/issues/7383

Basic information

Type: reviewed
Severity: critical
Advisory on GitHub: Open advisory ↗
Repository advisory: Open repository advisory ↗
Source code: Browse source ↗
Published (advisory): 2026-05-19 14:35:05 UTC
Updated: 2026-05-19 14:35:07 UTC
GitHub reviewed: 2026-05-19 14:35:05 UTC

CVSS Scores

Base score	Version	Severity	Vector
9.6	3.1	—	`CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H` Click to expand Attack vector (AV:N) Could be attacked over the internet or any normal routed network—not just someone sitting at the machine. Attack complexity (AC:L) Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup. Privileges required (PR:N) No account or special rights needed—anonymous or random user is enough. User interaction (UI:R) A real person has to do something—click, install, enable—otherwise it doesn’t land. Scope (S:C) Breaking this can reach past the original component and bite other resources—bigger blast radius. Confidentiality (C:H) Serious risk that confidential data gets exposed in a big way. Integrity (I:H) They could widely tamper with or forge data—trust in the data is badly hurt. Availability (A:H) Could take the service down hard or make it unusable for people who depend on it.

Identifiers

Type	Value
GHSA	GHSA-27f5-xjrr-q9ff ↗

CWEs

CWE id	Name
CWE-506	Embedded Malicious Code

Affected packages (4)

Vulnerable version ranges and first patched releases as published by GitHub.

Ecosystem	Package	Vulnerable range	First patched	Vulnerable functions
npm	@opensearch-project/opensearch	= 3.5.3	—	—
npm	@opensearch-project/opensearch	= 3.6.2	—	—
npm	@opensearch-project/opensearch	= 3.7.0	—	—
npm	@opensearch-project/opensearch	= 3.8.0	—	—