ETK-2026-3822Zero's internal tracking ID, independent of the CVE number.
waiting for further signalsZero needs more public information before it can validate it.description
cbor2 5.9.0 is affected by a use-after-free in its C-based CBOR decoder. An attacker able to supply a truncated, large definite-length text string for decoding can corrupt memory and crash the Python process.
mitigation
Upgrade cbor2 to version 6.0.0 or later. Until upgrading, do not decode untrusted CBOR input with cbor2 5.9.0.
fixed in 6.0.0
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.
- 2026-11-07 10:16Zghsa: trigger signal, started the run
- 2026-11-07 10:16Z
this entry in the feed
GET /api/v1/feed/ETK-2026-3822
{ "etk_id": "ETK-2026-3822", "cve_id": null, "display_id": "ETK-2026-3822", "ghsa_id": "GHSA-gg4m-grc6-63f2", "euvd_id": null, "status": "published", "anchor_state": "awaiting_cve", "title": "Use-after-free in cbor2 C decoder", "summary": "cbor2 5.9.0 is affected by a use-after-free in its C-based CBOR decoder. An attacker able to supply a truncated, large definite-length text string for decoding can corrupt memory and crash the Python process.", "mitigation": "Upgrade cbor2 to version 6.0.0 or later. Until upgrading, do not decode untrusted CBOR input with cbor2 5.9.0.", "vendor": "pip", "product": "pip:cbor2", "affected": [ { "affected_notes": [], "affected_ranges": [ "<=5.9.0" ], "ecosystem": "pip", "fixed_versions": [ "6.0.0" ], "package_name": "cbor2", "purl": "pkg:pypi/cbor2" } ], "cwes": [ 415 ], "cvss_score": 7.5, "cvss_src": "cna_vendor", "cvss_vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "epss_score": null, "epss_percentile": null, "epss_asof": null, "automation": "contextual", "check": false, "check_confidence_basis": null, "exploit": false, "pipeline_minutes": 8.6077224, "t0_at": null, "signals": { "public_poc": { "at": "2026-11-07T10:16:55+00:00", "days": -0.6071368102199074, "is_lower_bound": true, "measured_at": "2026-11-08T00:51:11.675342+00:00", "url": "https://github.com/agronholm/cbor2/security/advisories/GHSA-gg4m-grc6-63f2" }, "trigger_signal": { "at": "2026-11-07T10:16:55+00:00", "days": -0.6071368102199074, "is_lower_bound": true, "measured_at": "2026-11-08T00:51:11.675342+00:00", "url": "https://github.com/agronholm/cbor2/security/advisories/GHSA-gg4m-grc6-63f2" } } }
published 2026-11-07 10:42Z
last change 2026-11-08 00:40Z
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