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Fencer Intel
critical 9.6

GHSA-27f5-xjrr-q9ff json

Malware in @opensearch-project/opensearch

published 5mo ago modified 2mo ago

cvss
9.6
version 3.1, GitHub
cisa kev
Not listed
not in CISA's catalog
epss
—
no score, EPSS covers CVEs only
public exploits
0
none known

Summary

## 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

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CVSS scores

assigned by version score vector
GitHub 3.1 9.6 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H

Affected packages

ecosystem package affected fixed in
npm @opensearch-project/opensearch
1 listed version
 no fix listed

Classification

Weakness

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

The maintainers of opensearch-project/opensearch-js published their own advisory on GitHub. Reviewed sources take precedence over it.