CVE-2026-56329

Capgo - Cross-Tenant Preview Namespace Collision via Non-Bijective Underscore Decoding

MEDIUM
6.4
CVSS Score
Published: July 10, 2026 at 01:57 PM UTC
Updated: July 10, 2026 at 05:17 PM UTC
1 product affected across 1 vendorCapgo

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Severity
MEDIUM6.4
Exploit prediction
EPSS 0.3%
SSVC
PoC

Description

Capgo before 12.128.2 contains a cross-tenant preview namespace collision vulnerability caused by non-bijective decoding of double underscores to dots in preview hostname parsing. Attackers can register app IDs with underscores that collide with other tenants' dotted app IDs, causing preview misrouting and denial of preview access for victim applications.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 12.128.2
Vendor states this is fixed in 12.128.2 (unaffected)

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

SSVC — Action Prioritization

SSVCPoCNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

6.4MEDIUMVulnCheck
Attack Vector
NETWORK
Complexity
LOW
Privileges
LOW
User Interaction
NONE
Scope
CHANGED
Confidentiality
NONE
Integrity
LOW
Availability
LOW
Vector?

Quick Info

StatusDEFERRED
CWE
CWE-436

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