ETK-2026-4350Zero's internal tracking ID, independent of the CVE number.
waiting for further signalsZero needs more public information before it can validate it.description
Puma can leave worker threads blocked when an unauthenticated client stops reading a TLS response or a file response larger than 64 KB. An attacker can exhaust a worker's available threads and deny service where Puma terminates TLS itself or serves qualifying file responses.
mitigation
Upgrade Puma to 7.2.2 or 8.0.3. Until upgraded, terminate TLS at a reverse proxy or load balancer and serve static files there or keep proxy response buffering enabled.
fixed in 7.2.2, 8.0.3
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-2026-4350
{ "etk_id": "ETK-2026-4350", "cve_id": null, "display_id": "ETK-2026-4350", "ghsa_id": "GHSA-x646-wp7c-h9mg", "euvd_id": null, "status": "published", "anchor_state": "awaiting_cve", "title": "Unauthenticated worker-thread exhaustion in Puma", "summary": "Puma can leave worker threads blocked when an unauthenticated client stops reading a TLS response or a file response larger than 64 KB. An attacker can exhaust a worker's available threads and deny service where Puma terminates TLS itself or serves qualifying file responses.", "mitigation": "Upgrade Puma to 7.2.2 or 8.0.3. Until upgraded, terminate TLS at a reverse proxy or load balancer and serve static files there or keep proxy response buffering enabled.", "vendor": "rubygems", "product": "rubygems:puma", "affected": [ { "affected_notes": [], "affected_ranges": [ ">= 3.9.0, < 7.2.2" ], "ecosystem": "rubygems", "fixed_versions": [ "7.2.2" ], "package_name": "puma", "purl": "pkg:gem/puma" }, { "affected_notes": [], "affected_ranges": [ ">= 8.0.0, < 8.0.3" ], "ecosystem": "rubygems", "fixed_versions": [ "8.0.3" ], "package_name": "puma", "purl": "pkg:gem/puma" } ], "cwes": [ 400 ], "cvss_score": 8.7, "cvss_src": "cna_vendor", "cvss_vector": "CVSS:4.0/AV:N/AC:L/AT:N/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": 17.976439233333334, "t0_at": null, "signals": { "trigger_signal": { "at": "2026-11-13T05:12:49+00:00", "days": -0.10621526047453704, "is_lower_bound": true, "measured_at": "2026-11-13T07:45:46.063260+00:00", "url": "https://github.com/puma/puma/security/advisories/GHSA-x646-wp7c-h9mg" } } }
published 2026-11-13 05:31Z
last change 2026-11-13 07:43Z
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