ETK-2026-1344Zero's internal tracking ID, independent of the CVE number.

waiting for further signalsZero needs more public information before it can validate it.

GHSA-fpmh-frq8-7rj8 ↗

no check availablenot proven exploitable
awaiting cvepublic pocExploit code has been published by someone. Source signals can also carry a PoC (Proof of Concept).−8.8dkevAttacks confirmed in the real world.
go:klauspost/compress/zstd <= v1.20.1
fixed in v1.20.2
ETK-2026-1344Zero's internal tracking ID, independent of the CVE number., no cve assigned
pkg:golang/klauspost/compress/zstd
cvss7.0ethiack provisional
8d 17h 18msince last run
16mAI analysisAnalysis: how long the AI spent reversing this signal.
timeline
0 = trigger signal
trigger signal +0dpublic poc+0dwaiting for further signals+0.0d
0
+2d
+4d
+6d
+8d

description

klauspost/compress/zstd before v1.20.2 can panic while decoding specially malformed zstd frames. An attacker can cause a process crash when the application passes untrusted zstd-compressed input to the decoder.

mitigation

Upgrade github.com/klauspost/compress/zstd to v1.20.2 or later. Until upgrading, avoid decoding zstd data from untrusted sources or isolate decoding failures from critical processes.

fixed in v1.20.2

check
no
exploit
no
automationDeterministic: a check that runs on its own, the same request on every target. Contextual: an agentic technique that needs to be applied per target, for bugs that depend on contextual flows.
–
auth requiredWhether an attacker needs an account first, based on the CVSS vector's Privileges Required.
–
EPSSEstimate of the chance this CVE is exploited in the next 30 days. Refreshed daily.
–
agent run time
16m
cve.org record, t = 0The moment cve.org publishes the CVE in full.
not published yet
Δ to public pocExploit code has been published by someone. Source signals can also carry a PoC (Proof of Concept).
−8.8d
Δ to kevAttacks confirmed in the real world.
–

outcome

No artifact: an exploit or check was attempted but could not be produced at this moment.

source signals

Public signals that triggered or updated the pipeline. These are inputs for the deltas above.

  1. 2026-10-12 10:23Z
  2. 2026-10-12 10:23Z

this entry in the feed

GET /api/v1/feed/ETK-2026-1344

{
  "etk_id": "ETK-2026-1344",
  "cve_id": null,
  "display_id": "ETK-2026-1344",
  "ghsa_id": "GHSA-fpmh-frq8-7rj8",
  "euvd_id": null,
  "status": "published",
  "anchor_state": "awaiting_cve",
  "title": "Malformed-input panic in klauspost/compress zstd decoder",
  "summary": "klauspost/compress/zstd before v1.20.2 can panic while decoding specially malformed zstd frames. An attacker can cause a process crash when the application passes untrusted zstd-compressed input to the decoder.",
  "mitigation": "Upgrade github.com/klauspost/compress/zstd to v1.20.2 or later. Until upgrading, avoid decoding zstd data from untrusted sources or isolate decoding failures from critical processes.",
  "vendor": "go",
  "product": "go:klauspost/compress/zstd",
  "affected": [
    {
      "affected_notes": [],
      "affected_ranges": [
        "<= v1.20.1"
      ],
      "ecosystem": "go",
      "fixed_versions": [
        "v1.20.2"
      ],
      "package_name": "klauspost/compress/zstd",
      "purl": "pkg:golang/klauspost/compress/zstd"
    }
  ],
  "cwes": null,
  "cvss_score": 7,
  "cvss_src": "ethiack_provisional",
  "cvss_vector": null,
  "epss_score": null,
  "epss_percentile": null,
  "epss_asof": null,
  "automation": "deterministic",
  "check": false,
  "check_confidence_basis": null,
  "exploit": false,
  "pipeline_minutes": 15.965659566666666,
  "t0_at": null,
  "signals": {
    "public_poc": {
      "at": "2026-10-12T10:23:05+00:00",
      "days": -8.76966476,
      "is_lower_bound": true,
      "measured_at": "2026-10-21T04:51:24.057412+00:00",
      "url": "https://github.com/klauspost/compress/security/advisories/GHSA-fpmh-frq8-7rj8"
    },
    "trigger_signal": {
      "at": "2026-10-12T10:23:05+00:00",
      "days": -8.76966476,
      "is_lower_bound": true,
      "measured_at": "2026-10-21T04:51:24.057412+00:00",
      "url": "https://github.com/klauspost/compress/security/advisories/GHSA-fpmh-frq8-7rj8"
    }
  }
}

published 2026-10-12 11:17Z
last change 2026-10-21 04:45Z

Need the technical details behind an entry?

Every entry here shows what we attempted and when. The technical details, the generated exploit that fired it and the evidence behind the verdict are not public. Tell us about your use case and we’ll get back to you about extended API access.