CVE-2026-55622

CVE-2026-55622 is an authorization bypass in Incus where an authenticated user can copy an instance from a project they have write access to into a different project they legitimately belong to — without having read access to the source project's instance. The copy operation only checked authorization on the write to the target project, not the read of source project state. This meant any user who knew or could guess a project name and instance name (both likely discoverable through normal usage in documentation, error messages, and API responses) could exfiltrate that instance's full state: configuration, secrets, credentials, and network trust relationships. The critical underweighting in severity assessments is the cascade, not the initial access. A copied instance isn't just a data blob — it's a persistent foothold that inherits every downstream trust relationship the original held: service account tokens for internal APIs, network trust paths, stored credentials that unlock other systems. The privilege escalation compounds through everything that instance can reach. The CVE description frames this as 'access to secrets,' but the real blast radius is the foothold that survives in the target project. The patch in version 7.2.0 adds a source-read authorization check to the copy operation. What it doesn't disclose is whether this was a targeted fix or part of a broader audit. The same implicit-trust gap likely exists in snapshot, migration, and backup-restore operations across projects — all are state-transfer operations that require reading source state before writing to a destination. If the vendor only patched copy, the sibling operations remain exploitable. Audit logs are your detection mechanism: determine whether Incus emits events when instances are copied into a project. If target-project admins receive no alert, attackers get extended dwell time with no detection signal. The deeper question is whether the copy-across-projects capability should exist at all, or whether it was a legacy migration feature that predates Incus's multi-tenant security model and was never re-evaluated when project boundaries became security boundaries.

Reviewed through automated stages and approved by a human before publication.