Google Compute Engine CVE-2026-85299

Requires an authenticated Google Cloud principal with the ability to call the disks.createSnapshot or regionDisks.createSnapshot APIs; exploitation consists of targeting a disk in a different (victim) project, where the missing authorization check (CWE-862) allowed the cross-project snapshot to proceed. Limiting factors: valid GCP credentials are required (PR:L, so not anonymous/unauthenticated), the impact is confined to confidentiality of disk data, and most importantly Google states the flaw was remediated server-side on 2026-08-31 with no customer action needed, so current Compute Engine deployments are not exploitable and the exposure window is historical (any GCE usage predating the 2026-08-31 fix).

Signals are mostly consistent and point to a genuine but bounded-severity authorization flaw rather than a mass-exploitation emergency. The CVSS 4.0 vector (AV:N/AC:L/AT:N/PR:L/UI:N) describes a network-reachable, low-complexity attack requiring low privileges, i.e. an authenticated GCP principal; impact is confidentiality-only (VC:H) with a subsequent-system confidentiality impact (SC:H) reflecting cross-project data exposure, and no integrity or availability impact (VI:N/VA:N/SI:N/SA:N). EPSS is low (0.35%, 29th percentile), there is no CISA KEV listing and no public exploit or PoC reference in the input, so there is no public exploit identified at time of analysis and no evidence of active exploitation. The vuln.today decision label is this_week, which fits a real-but-not-emergency authorization bug. The single most important mitigating fact is that Google states the issue was patched platform-side on 2026-08-31 with no customer action needed, so current GCE deployments are not exploitable; the residual risk is historical (data that may have been accessed before the fix). No major conflicts exist between signals, though the Tags label this an Authentication Bypass while the CWE (CWE-862) and description describe Missing Authorization, which are distinct classes.

An attacker with a valid, low-privileged Google Cloud identity invokes the disks.createSnapshot or regionDisks.createSnapshot API against a disk belonging to a different project. Because the authorization check was missing, the call succeeds despite the attacker lacking rights in the victim project, yielding a snapshot of the target disk and allowing exfiltration of its data. No public exploit code or PoC reference is present in the supplied data, and Google reports the flaw was fixed server-side on 2026-08-31.