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CVE

CVE-2026-82021

Hermes Agent 0.18.2 < 0.19.0 MCP Catalog Supply Chain RCE via Mutable Branch Reference
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CVE

CVE-2026-82021

Hermes Agent 0.18.2 < 0.19.0 MCP Catalog Supply Chain RCE via Mutable Branch Reference

Hermes Agent 0.18.2 prior to 0.19.0 contains a supply chain vulnerability in its bundled MCP catalog that allows a remote attacker to execute arbitrary code by compromising a third-party upstream repository referenced via a mutable branch rather than a pinned commit SHA. An attacker who compromises the upstream repository can propagate malicious code to every host that installs the affected catalog entry, with no further action required by the operator.

Package Versions Affected

Package Version
patch Availability
No items found.

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CVSS Version

Severity
Base Score
CVSS Version
Score Vector
C
H
U
9
-
4.0
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
C
H
U
0
-
C
H
U
-

Related Resources

No items found.

References

https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/82xxx/CVE-2026-82021.json, https://github.com/NousResearch/hermes-agent/releases/tag/v2026.7.20, https://nvd.nist.gov/vuln/detail/CVE-2026-82021, https://www.vulncheck.com/advisories/hermes-agent-mcp-catalog-supply-chain-rce-via-mutable-branch-reference, https://github.com/NousResearch/hermes-agent/commit/9df5f879b4a5925c0f8f947e7e16ed8e845932c3, https://github.com/NousResearch/hermes-agent/pull/64463, https://github.com/NousResearch/hermes-agent

Severity

0

CVSS Score
0
10

Basic Information

Base CVSS
0
EPSS Probability
0.00339%
EPSS Percentile
0.25227%
Introduced Version
9de9c25f620ff7f1ce0fd5457d596052d5159596
Fix Available
3ef6bbd201263d354fd83ec55b3c306ded2eb72a

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