knowns versions before 0.30.0 contain a path traversal vulnerability in the POST /api/templates/preview endpoint that allows unauthenticated attackers to read arbitrary files. Attackers can supply directory traversal sequences in the templateFile parameter to bypass path restrictions and read sensitive files like credentials and configuration through the JSON response.
CVE-2026-86538
Score 7.5 from GitHub Security Advisory (severity: HIGH) published 2026-09-08. the CNA's CVSS baseline 7.5; sources differ by 0.0.
- High severity, but no confirmed exploitation yet
No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.
- CVSS v3
- 7.5
- EG Score
- 7.5(high)
- EG Risk
- 49(Track)EG Risk 49/100SSVC: Track
EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).
How it’s computedSeverity75% × 45%Exploitation1% × 40%Automatability100% × 15%Action: Routine — remediate on your standard cadence. - EPSS PROB
- 1%
- EPSS %ILE
- 61%
- KEV
- Not listed
Published
September 7, 2026
Last Modified
September 24, 2026
Advisory Details (5)
Auto-updated Sep 7, 2026knowns before 0.30.0 Path Traversal via templateFile parameter | Advisories | VulnCheck
https://www.vulncheck.com/advisories/knowns-before-0.30.0-path-traversal-via-templatefile-parameterv0.30.0
Patch available: knowns-dev/knowns v0.30.0
https://github.com/knowns-dev/knowns/releases/tag/v0.30.0commit 09c5a96fd581 (knowns-dev/knowns)
Fix landed in knowns-dev/knowns commit 09c5a96fd581 — awaiting tagged release
https://github.com/knowns-dev/knowns/commit/09c5a96fd5817b941dc86669278c1a17db10ed4eknowns/internal/server/routes/templates.go at v0.29.1 · knowns-dev/knowns · GitHub
https://github.com/knowns-dev/knowns/blob/v0.29.1/internal/server/routes/templates.go#L299-L310Arbitrary File Read via POST /api/templates/preview templateFile · Advisory · knowns-dev/knowns · GitHub
https://github.com/knowns-dev/knowns/security/advisories/GHSA-fpxv-c555-rhm3Vendor Advisories for CVE-2026-86538(1)
These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.
Weakness Classification(1)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 28× in last 7d / 76× in last 30d)
Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.
- 2026-09-25 02:16 UTCGHSA enrichment
- 2026-09-24 14:53 UTCEG score recompute
- 2026-09-24 14:53 UTCGHSA enrichment
- 2026-09-24 14:04 UTCEPSS rescore
- 2026-09-24 11:31 UTCGHSA enrichment
- 2026-09-24 00:09 UTCEG score recompute
- 2026-09-24 00:09 UTCGHSA enrichment
- 2026-09-23 17:54 UTCEPSS rescore
- 2026-09-23 12:47 UTCGHSA enrichment
- 2026-09-23 01:25 UTCEG score recompute
- 2026-09-23 01:25 UTCGHSA enrichment
- 2026-09-22 16:01 UTCEPSS rescore
- 2026-09-22 14:03 UTCGHSA enrichment
- 2026-09-22 02:41 UTCEG score recompute
- 2026-09-22 02:41 UTCGHSA enrichment
- 2026-09-21 21:09 UTCEPSS rescore
- 2026-09-21 15:17 UTCGHSA enrichment
- 2026-09-21 03:55 UTCEG score recompute
- 2026-09-21 03:55 UTCGHSA enrichment
- 2026-09-20 20:16 UTCEPSS rescore
- 2026-09-20 16:33 UTCGHSA enrichment
- 2026-09-20 05:11 UTCGHSA enrichment
- 2026-09-19 17:49 UTCEG score recompute
- 2026-09-19 17:49 UTCGHSA enrichment
- 2026-09-19 06:27 UTCEG score recompute
Show 51 moreShow fewer
- 2026-09-19 06:26 UTCGHSA enrichment
- 2026-09-18 19:28 UTCEPSS rescore
- 2026-09-18 19:04 UTCGHSA enrichment
- 2026-09-18 07:42 UTCGHSA enrichment
- 2026-09-17 20:20 UTCEG score recompute
- 2026-09-17 20:20 UTCGHSA enrichment
- 2026-09-17 19:32 UTCEPSS rescore
- 2026-09-17 05:44 UTCGHSA enrichment
- 2026-09-16 18:19 UTCEG score recompute
- 2026-09-16 18:19 UTCGHSA enrichment
- 2026-09-16 14:09 UTCEPSS rescore
- 2026-09-16 06:32 UTCEG score recompute
- 2026-09-16 06:32 UTCGHSA enrichment
- 2026-09-16 05:15 UTCEPSS rescore
- 2026-09-15 19:11 UTCGHSA enrichment
- 2026-09-15 07:49 UTCEG score recompute
- 2026-09-15 07:49 UTCGHSA enrichment
- 2026-09-15 03:12 UTCEPSS rescore
- 2026-09-15 03:12 UTCEPSS rescore
- 2026-09-14 20:27 UTCEG score recompute
- 2026-09-14 20:27 UTCGHSA enrichment
- 2026-09-14 19:40 UTCEG score recompute
- 2026-09-14 19:40 UTCGHSA enrichment
- 2026-09-14 19:28 UTCGHSA enrichment
- 2026-09-14 08:06 UTCGHSA enrichment
- 2026-09-13 20:44 UTCEG score recompute
- 2026-09-13 20:44 UTCGHSA enrichment
- 2026-09-13 09:21 UTCGHSA enrichment
- 2026-09-12 21:59 UTCEG score recompute
- 2026-09-12 21:59 UTCGHSA enrichment
- 2026-09-12 10:36 UTCGHSA enrichment
- 2026-09-11 23:13 UTCEG score recompute
- 2026-09-11 23:13 UTCGHSA enrichment
- 2026-09-11 14:53 UTCEPSS rescore
- 2026-09-11 14:53 UTCEPSS rescore
- 2026-09-11 11:19 UTCEG score recompute
- 2026-09-11 11:18 UTCGHSA enrichment
- 2026-09-11 05:03 UTCGHSA enrichment
- 2026-09-10 17:41 UTCEG score recompute
- 2026-09-10 17:41 UTCGHSA enrichment
- 2026-09-10 06:19 UTCGHSA enrichment
- 2026-09-09 18:57 UTCGHSA enrichment
- 2026-09-09 07:34 UTCEG score recompute
- 2026-09-09 07:34 UTCGHSA enrichment
- 2026-09-08 22:01 UTCEPSS rescore
- 2026-09-08 20:12 UTCGHSA enrichment
- 2026-09-08 10:59 UTCEG score recompute
- 2026-09-08 10:59 UTCGHSA enrichment
- 2026-09-07 23:35 UTCEG score recompute
- 2026-09-07 23:07 UTCEG score recompute
- 2026-09-07 23:06 UTCMITRE cvelistV5first tracked
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Frequently asked(5)
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