criticalCVSS 9.6Vulnerability

GHSA-27f5-xjrr-q9ff

## 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/security/advisories/GHSA-g7cv-rxg3-hmpx) https://github.com/TanStack/router/issues/7383

Properties

ghsa_id
GHSA-27f5-xjrr-q9ff
severity
critical
summary
Malware in @opensearch-project/opensearch
cvss_score
9.6
cve_id
GHSA-27f5-xjrr-q9ff
cvss_vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
is_ghsa_only
true
ghsa_published
2026-05-19T14:35:05Z
source_url
https://github.com/advisories/GHSA-27f5-xjrr-q9ff
ghsa_updated
2026-05-19T14:35:07Z

Related Entities (4)

REPORTED_BY (1)

[Source]GitHub Advisory Database

VULNERABLE_TO (1)

[Software]npm/@opensearch-project/opensearch

AFFECTS (1)

[Software]npm/@opensearch-project/opensearch

HAS_WEAKNESS (1)

[Weakness]Embedded Malicious Code

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