ETK-2026-4385Zero's internal tracking ID, independent of the CVE number.
waiting for further signalsZero needs more public information before it can validate it.description
Puma releases before 7.2.2 or 8.0.3 can let an unauthenticated client stall a worker's reactor, delaying service for connections managed by that worker. Exposure exists with the default settings when Puma is directly reachable by untrusted clients and the application has an endpoint with client-influenced response size. A response-buffering reverse proxy prevents this condition.
mitigation
Upgrade Puma to 7.2.2 or 8.0.3. Until upgraded, place Puma behind a reverse proxy that buffers requests and responses, and do not expose its listener directly to untrusted clients.
fixed in 8.0.3, 7.2.2
outcome
Contextual, not validated: no deterministic check could cover this one, and no technique passed our review.
source signals
Public signals that triggered or updated the pipeline. These are inputs for the deltas above.
- 2026-11-13 05:12Zghsa: trigger signal, started the run
this entry in the feed
GET /api/v1/feed/ETK-2026-4385
{ "etk_id": "ETK-2026-4385", "cve_id": null, "display_id": "ETK-2026-4385", "ghsa_id": "GHSA-xw3h-pgr9-3vg7", "euvd_id": null, "status": "published", "anchor_state": "awaiting_cve", "title": "Blocking-write denial of service in Puma reactor", "summary": "Puma releases before 7.2.2 or 8.0.3 can let an unauthenticated client stall a worker's reactor, delaying service for connections managed by that worker. Exposure exists with the default settings when Puma is directly reachable by untrusted clients and the application has an endpoint with client-influenced response size. A response-buffering reverse proxy prevents this condition.", "mitigation": "Upgrade Puma to 7.2.2 or 8.0.3. Until upgraded, place Puma behind a reverse proxy that buffers requests and responses, and do not expose its listener directly to untrusted clients.", "vendor": "rubygems", "product": "rubygems:puma", "affected": [ { "affected_notes": [], "affected_ranges": [ ">= 8.0.0, < 8.0.3" ], "ecosystem": "rubygems", "fixed_versions": [ "8.0.3" ], "package_name": "puma", "purl": "pkg:gem/puma" }, { "affected_notes": [], "affected_ranges": [ ">= 3.8.0, < 7.2.2" ], "ecosystem": "rubygems", "fixed_versions": [ "7.2.2" ], "package_name": "puma", "purl": "pkg:gem/puma" } ], "cwes": [ 400 ], "cvss_score": 8.2, "cvss_src": "cna_vendor", "cvss_vector": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N", "epss_score": null, "epss_percentile": null, "epss_asof": null, "automation": "contextual", "check": false, "check_confidence_basis": null, "exploit": false, "pipeline_minutes": 13.27447035, "t0_at": null, "signals": { "trigger_signal": { "at": "2026-11-13T05:12:20+00:00", "days": -1.0107246886574075, "is_lower_bound": true, "measured_at": "2026-11-14T05:27:46.706987+00:00", "url": "https://github.com/puma/puma/security/advisories/GHSA-xw3h-pgr9-3vg7" } } }
published 2026-11-13 13:19Z
last change 2026-11-14 05:26Z
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