CVE-2026-103476

MEDIUMPre-NVD 5.35.3—
EchelonGraph scoreHIGH confidence

Score 5.3 from GitHub Security Advisory published 2026-09-30. A secondary CVSS source baseline 5.3; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
Trending — 4 sources updated this week
5.3EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0.3%CVSS: 5.3Exploit: None knownExposed services: Not assessed

No fix is confirmed yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for the fix.

yii2-starter-kit through 4.2.0 fails to validate article publication status in the attachment-download endpoint, allowing unauthenticated attackers to download files from draft articles. Attackers can enumerate sequential attachment identifiers to retrieve files from unpublished articles without authentication or authorization checks.

CVSS v3
5.3
EG Score
5.3MEDIUMhigh confidence
EG Risk
39
EG Risk 39/100CISA SSVC

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 computed
Severity53% × 45%
Exploitation0% × 40%
Automatability100% × 15%
CISA SSVC: Track at low or medium mission impact; Attend at high (mission-essential systems).
Action: No fix is confirmed yet. Restrict network exposure of the affected system or apply the vendor's mitigation within your standard update timelines at low or medium mission impact and sooner than that at high, and watch the vendor's advisory for the fix.
EPSS PROB
0.3%
EPSS %ILE
19th
KEV
Not listed

CISA SSVCTrack at low or medium mission impact; Attend at high (mission-essential systems).

No fix is confirmed yet. Restrict network exposure of the affected system or apply the vendor's mitigation within your standard update timelines at low or medium mission impact and sooner than that at high, and watch the vendor's advisory for the fix.

Exploitation none (CISA Vulnrichment) · Automatable yes (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). Mission impact is CISA's Mission & Well-being decision point, and only you can judge it: high means the affected system is essential to your organisation's mission, or its compromise could cause irreversible harm to people. CISA's decision table

Published

September 30, 2026

Last Modified

October 1, 2026

Advisory Details (4)

Auto-updated Sep 30, 2026
No patch confirmed yet.
generic

yii2-starter-kit through 4.2.0 Unauthorized File Download via attachment-download | Advisories | VulnCheck

https://www.vulncheck.com/advisories/yii2-starter-kit-through-4.2.0-unauthorized-file-download-via-attachment-download
generic

yii2-starter-kit/frontend/controllers/ArticleController.php at cc2c451e8c959c7300b04efea597706a38609f58 · yii-starter-kit/yii2-starter-kit · GitHub

https://github.com/yii-starter-kit/yii2-starter-kit/blob/cc2c451e8c959c7300b04efea597706a38609f58/frontend/controllers/ArticleController.php#L69
generic

GitHub - yii-starter-kit/yii2-starter-kit: Yii2 Starter Kit · GitHub

https://github.com/yii-starter-kit/yii2-starter-kit
generic

Security: unrestricted file upload, IDOR attachment download, debug/gii exposure · Issue #797 · yii-starter-kit/yii2-starter-kit · GitHub

https://github.com/yii-starter-kit/yii2-starter-kit/issues/797

Vendor Advisories for CVE-2026-103476(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 15× in last 7d / 15× 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.

  1. 2026-10-03 19:16 UTCEG score recompute
  2. 2026-10-03 19:16 UTCGHSA enrichment
  3. 2026-10-03 14:25 UTCEPSS rescore
  4. 2026-10-02 17:56 UTCEG score recompute
  5. 2026-10-02 17:56 UTCGHSA enrichment
  6. 2026-10-01 19:49 UTCEPSS rescore
  7. 2026-10-01 16:36 UTCEG score recompute
  8. 2026-10-01 16:36 UTCGHSA enrichment
  9. 2026-10-01 15:41 UTCEG score recompute
  10. 2026-10-01 15:41 UTCGHSA enrichment
  11. 2026-09-30 19:12 UTCEG score recompute
  12. 2026-09-30 19:12 UTCGHSA enrichment
  13. 2026-09-30 18:25 UTCEG score recompute
  14. 2026-09-30 17:36 UTCEG score recompute
  15. 2026-09-30 17:35 UTCMITRE cvelistV5first tracked

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-103476?
CVE-2026-103476 is a medium vulnerability published on September 30, 2026. yii2-starter-kit through 4.2.0 fails to validate article publication status in the attachment-download endpoint, allowing unauthenticated attackers to download files from draft articles. Attackers can enumerate sequential attachment identifiers to retrieve files from unpublished articles without…
When was CVE-2026-103476 disclosed?
CVE-2026-103476 was first published on September 30, 2026, with the most recent update on October 1, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-103476 actively exploited?
CVE-2026-103476 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.3% probability of exploitation in the next 30 days (19th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-103476?
CVE-2026-103476 has a CVSS base score of 5.3 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
How do I remediate CVE-2026-103476?
No fix for CVE-2026-103476 is confirmed yet. Until one is published, restrict network exposure of the affected system or apply the vendor's mitigation — for example, keep it off the internet or limit it to trusted networks — and watch the vendor's advisory for the fix. The vendor advisories EchelonGraph has for CVE-2026-103476 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

Explore the affected products and dependency analysis for CVE-2026-103476

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