CVE-2026-13591Public exploitNetwork attack vector

Trusted-message spoofing via channel-agnostic contact tracking

Published Jun 29, 2026 · Updated Jun 29, 2026

Improper authorization in DeepMyst Mysti 0.4.0 allows remote authenticated users to inject messages through a connected channel. ChannelBridge tracks contacts only by a normalized sender value, and _isTrackedConversation ignores channel identity when authorizing inbound routing. Exploitation requires another connected channel or control of inbound sender metadata; accepted messages can spoof replies, alter agent context, or interrupt tasks.

CVSS severityUnavailable
Unscored
EPSS probability0.32%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Improper authorization in DeepMyst Mysti 0.4.0 allows remote authenticated users to inject messages through a connected channel. ChannelBridge tracks contacts only by a normalized sender value, and _isTrackedConversation ignores channel identity when authorizing inbound routing. Exploitation requires another connected channel or control of inbound sender metadata; accepted messages can spoof replies, alter agent context, or interrupt tasks.

The record

CVE
CVE-2026-13591
Published
Jun 29, 2026
Updated
Jun 29, 2026
Vendor
DeepMyst
Product
Mysti
Classifications
CWE-266, CWE-285
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Jun 29, 2026CVE publishedPublication date reported by the CVE source.
  2. Jun 29, 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=0.4.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

DeepMyst · Mystiversion=0.4.0

Published CVSS scores

5.0VulDB CNACVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:L/E:P/RL:O/RC:C
2.3VulDB CNACVSS:4.0/AV:N/AC:H/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P
4.6VulDB CNAAV:N/AC:H/Au:S/C:P/I:P/A:P/E:POC/RL:OF/RC:C
5.0VulDB CNACVSS:3.0/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:L/E:P/RL:O/RC:C

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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-266Incorrect Privilege Assignment
CWE-285Improper Authorization

Public exploit references

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

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo