CVE-2026-90454Network attack vectorHinoki check available

Session-tag tampering via incomplete route denylist

Published Sep 11, 2026 · Updated Sep 11, 2026

Authorization bypass in Malcolm before 26.06.0 allows remote authenticated users to alter tags on stored Arkime session records. The deny regex in nginx_readonly.conf omits the sessions/addtags and sessions/removetags paths while its method rule permits POST requests. Access requires valid Malcolm credentials and a deployment using the read-only Nginx configuration; the effect is limited to forensic session-tag integrity.

CVSS severityUnavailable
Unscored
EPSS probability0.21%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Authorization bypass in Malcolm before 26.06.0 allows remote authenticated users to alter tags on stored Arkime session records. The deny regex in nginx_readonly.conf omits the sessions/addtags and sessions/removetags paths while its method rule permits POST requests. Access requires valid Malcolm credentials and a deployment using the read-only Nginx configuration; the effect is limited to forensic session-tag integrity.

The record

CVE
CVE-2026-90454
Published
Sep 11, 2026
Updated
Sep 11, 2026
Vendor
Cybersecurity and Infrastructure Security Agency (CISA)
Product
Malcolm
Classifications
T1565.001
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Sep 11, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 11, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

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

  1. Affected versionversion=0 <v26.06.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Cybersecurity and Infrastructure Security Agency (CISA) · Malcolmversion=0 <v26.06.0

Published CVSS scores

No CVSS assessment is available in this record.

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.

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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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1565.001Stored Data Manipulation

Public exploit references

No public exploit references are available in this record.

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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