CVE-2026-10221Public exploitNetwork attack vector

Remote injection through context compression

Published Jun 1, 2026 · Updated Jun 1, 2026

Injection in _compress_context in Nous Research Hermes Agent 0.12.0 and earlier allows remote attackers to inject content via context compression. The CNA identifies the function and file but does not disclose which input reaches the compression path or which downstream syntax interprets it. Remote attackers require no authentication or user interaction, but published material does not identify the resulting action beyond injection.

CVSS severity7.3
High
EPSS probability0.30%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Injection in _compress_context in Nous Research Hermes Agent 0.12.0 and earlier allows remote attackers to inject content via context compression. The CNA identifies the function and file but does not disclose which input reaches the compression path or which downstream syntax interprets it. Remote attackers require no authentication or user interaction, but published material does not identify the resulting action beyond injection.

The record

CVE
CVE-2026-10221
Published
Jun 1, 2026
Updated
Jun 1, 2026
Vendor
Nous Research
Product
Hermes Agent
Classifications
CWE-707, CWE-74
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 1, 2026CVE publishedPublication date reported by the CVE source.
  2. Jun 1, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0.1
  2. Affected versionversion=0.10
  3. Affected versionversion=0.11
  4. Affected versionversion=0.12.0
  5. Affected versionversion=0.2
  6. Affected versionversion=0.3
  7. Affected versionversion=0.4
  8. Affected versionversion=0.5
  9. Affected versionversion=0.6
  10. Affected versionversion=0.7
  11. Affected versionversion=0.8
  12. Affected versionversion=0.9

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Nous Research · Hermes Agentversion=0.1; version=0.10; version=0.11; version=0.12.0; version=0.2; version=0.3; version=0.4; version=0.5; version=0.6; version=0.7; version=0.8; version=0.9

Published CVSS scores

7.3VulDBCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
7.5VulDBAV:N/AC:L/Au:N/C:P/I:P/A:P
5.5VulDBCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-707Improper Neutralization
CWE-74Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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