{"items":[{"id":"NVI-00016051","kind":"vulnerability","title":"Pomerium Pre-Auth Memory Exhaustion via Unbounded zstd Decompression in HPKE Callback","revision":1,"unknowns":["Customer inventory, deployment, reachability and exploitation have not been inspected."],"lifecycle":"active","identifiers":["GHSA-ggw3-5987-rx77","CVE-2026-50285"],"plain_summary":"GitHub lists this reviewed advisory for github.com/pomerium/pomerium. Published version ranges and source prerequisites are shown below; this is not an inspection of a visitor’s application.","review_status":"source_listed","control_topics":[],"public_actions":[{"summary":"Identify the exact component and deployed version, examine the linked publisher’s conditions, and retain evidence of any mitigation.","source_ids":["sr-0fda6aa8ed92feb09028d9c7874a8948"],"action_type":"investigate","limitations":"Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system.","current_supported_target":null}],"schema_version":"1.1.0","source_metrics":[{"kind":"CVSS","as_of":"2026-07-15T23:08:18.000Z","value":"7.5 high","meaning":"GitHub source severity; exploitability and local consequence require separate evidence.","source_id":"sr-0fda6aa8ed92feb09028d9c7874a8948"}],"why_it_matters":"Published affected context helps an owner decide what evidence to gather. This report has not examined your application.","related_sources":[{"id":"sr-0fda6aa8ed92feb09028d9c7874a8948","url":"https://github.com/advisories/GHSA-ggw3-5987-rx77","basis":"vendor_advisory","notes":"GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.","title":"GHSA-ggw3-5987-rx77","publisher":"GitHub Advisory Database","observed_at":"2026-11-04T09:59:26.779Z"}],"affected_context":[{"certainty":"source_listed","source_ids":["sr-0fda6aa8ed92feb09028d9c7874a8948"],"technology":"github.com/pomerium/pomerium","known_exclusions":[],"conditions_summary":"## Summary\n\nThe HPKE V2 URL decode path in `pkg/hpke/url.go` decompresses attacker-controlled zstd data without any size limit. On Pomerium deployments using the stateless authentication flow (Pomerium Zero / hosted authenticate), the proxy's `/.pomerium/callback` endpoint is reachable without credentials and processes attacker-crafted HPKE-encrypted payloads before the sender's identity is validated. Because Pomerium's HPKE receiver public key is publicly served, an attacker can encrypt a decompression bomb, deliver it to the callback endpoint, and cause unbounded memory allocation — crashing or degrading the proxy process.\n\n## Severity\n\n**High** (CVSS 3.1: 7.5)\n\n`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H`\n\n- **Attack Vector:** Network — the `/.pomerium/callback` route on the proxy service is externally reachable.\n- **Attack Complexity:** Low — the receiver public key is publicly available at `/.well-known/pomerium/hpke-public-key`; no special conditions apply.\n- **Privileges Required:** None — the callback endpoint is intentionally pre-authentication (it is the OAuth landing page).\n- **User Interaction:** None\n- **Scope:** Unchanged — the DoS is confined to the Pomerium proxy ","public_affected_ranges":[">= 0.32.6, < 0.32.8"]}],"null_published_at":"2026-11-04T10:04:27.870Z","source_updated_at":"2026-07-15T23:08:18.000Z","source_disclosed_at":"2026-07-15T23:08:18.000Z","is_synthetic_fixture":false,"null_last_reviewed_at":null,"public_change_summary":"First indexed by Null; source disclosure date is shown separately.","null_first_observed_at":"2026-11-04T09:59:26.779Z"}],"next_cursor":null,"snapshot_revision":"42594"}