CVE-2026-13591

Exploitation

Public exploit code exists. CISA's assessment records a public proof of concept. That is not a report of exploitation in the wild.

SSVC decision

• ExploitationpocPublic proof-of-concept exploit code exists. Not a report of exploitation in the wild.
• AutomatablenoAt least one step from reconnaissance to exploitation cannot be reliably automated.
• Technical ImpactpartialSuccessful exploitation gives limited control of the vulnerable component.

CISA publishes the decision points, not a final SSVC decision. The decision also depends on mission and well-being impact, which is a property of your deployment rather than of the vulnerability.

EPSS probability

0.32% probability of exploitation activity in the next 30 days.

EPSS percentile

Ranks above 23.9% of scored records. A rank, not a probability.

NVD base score

1.3 (CVSS v4.0), scored by the NVD independently of the CNA.

NVD CVSS vector

CVSS: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/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

NVD analysis status

Deferred. NVD last modified this record on 2026-06-29.

Red Hat severity

No Red Hat rating. Red Hat rates the CVEs that affect its products.

Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.

Published

2026-06-29 17:00Z2 MO AGO

Last updated

2026-06-29 17:30Z2 MO AGO

Reserved

2026-06-29

Assigning CNA

VulDB

Record state

PUBLISHED

Severity

Low (CVSS 2.3)

CNA CVSS vector

CVSS: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

Weaknesses

• CWE-266Incorrect Privilege AssignmentBase
• CWE-285Improper AuthorizationClass

Data version

5.2

Document digest

1044acfff373743c96c87e0e507f49c6101878e1a3d764cb81cfc6fc31d2a16a

• vuldb.comVDB-374594 | DeepMyst Mysti Contact Tracking ChannelBridge.ts _isTrackedConversation improper authorizationhttps://vuldb.com/vuln/374594vdb-entrytechnical-description
• vuldb.comVDB-374594 | CTI Indicators (IOB, IOC, TTP, IOA)https://vuldb.com/vuln/374594/ctisignaturepermissions-required
• vuldb.comCVE-2026-13591 | CVE Analysis and Reporthttps://vuldb.com/cve/CVE-2026-13591third-party-advisory
• vuldb.comSubmit #844480 | DeepMyst Mysti 0.4.0 Authorization Bypass / Identity Spoofinghttps://vuldb.com/submit/844480third-party-advisory
• github.comhttps://github.com/DeepMyst/Mysti/issues/42exploitissue-tracking
• github.comhttps://github.com/DeepMyst/Mysti/pull/43issue-trackingpatch
• github.comhttps://github.com/DeepMyst/Mysti/commit/9b4aff0f106db424aa45a35aa89dd0b8f2eb9a48patch
• github.comhttps://github.com/DeepMyst/Mysti/product