SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityDeferred

CVE-2026-100617

Cap-go capgo.app fails to validate that principals in channel_permission_overrides belong to the organization, allowing authenticated app/org admins to grant channel permissions to non-member users.

HIGH 8.7EPSS 0.38%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.38%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

Cap-go capgo.app fails to validate that principals in channel_permission_overrides belong to the organization, allowing authenticated app/org admins to grant channel permissions to non-member users. Attackers with admin privileges can insert override rows with arbitrary external user UUIDs to grant channel-scoped permissions such as channel.promote_bundle to users outside the organization.

CVSS 4.0
8.7 HIGHCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
EPSS
0.38% probability · 32th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Weakness
CWE-862
Source
disclosure@vulncheck.com
EPSS trend
0%3%5%27 September 2026: 0.30%26 October 2026: 0.38%27 September 202626 October 2026

EPSS moved from 0.3% on 27 September 2026 to 0.4% on 26 October 2026.

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.