CVE-2026-100909

HIGHPre-NVD 7.37.3—
EchelonGraph scoreHIGH confidence

Score 7.3 from GitHub Security Advisory published 2026-09-28. A secondary CVSS source baseline 7.3; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
Trending — 5 sources updated this weekElevated
7.3EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0.3%CVSS: 7.3Exploit: Elevated riskExposed services: Not assessed

A fix is available — apply it.

A vulnerability was found in OctoberCMS up to 4.1.19/4.2.25/4.3.4. The impacted element is the function getSourcePathForResize of the file modules/system/classes/ResizeImages.php. The manipulation of the argument realSourcePath results in server-side request forgery. The attack may be performed from remote. The exploit has been made public and could be used. Upgrading to version 4.3.5 and 4.4.0 is sufficient to resolve this issue. The patch is identified as 0e9736aa2c6d6bd3d60ff6ef9e0b4d32ce387f58. The affected component should be upgraded.

CVSS v3
7.3
EG Score
7.3HIGHhigh confidence
EG Risk
64
EG Risk 64/100CISA 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
Severity73% × 45%
Exploitation40% × 40%
Automatability100% × 15%
CISA SSVC: Track at low or medium mission impact; Attend at high (mission-essential systems).
Action: A fix is available. Apply it within your standard update timelines at low or medium mission impact and sooner than that at high.
EPSS PROB
0.3%
EPSS %ILE
20th
KEV
Not listed

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

A fix is available. Apply it within your standard update timelines at low or medium mission impact and sooner than that at high.

Exploitation public PoC (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 28, 2026

Last Modified

September 28, 2026

Advisory Details (3)

Auto-updated Sep 28, 2026
🔬 Proof of concept available. Patch available. Sources: github, github_commit.
github_commit Patch Available

commit 0e9736aa2c6d (octobercms/october)

Patch available: octobercms/october v4.4.0 (contains commit 0e9736aa2c6d)

https://github.com/octobercms/october/commit/0e9736aa2c6d6bd3d60ff6ef9e0b4d32ce387f58
generic🟡 PoC Available

CVE/October_CMS_Stream_Wrapper_Injection.md at main · 0xGenesi/CVE · GitHub

https://github.com/0xGenesi/CVE/blob/main/October_CMS_Stream_Wrapper_Injection.md
github Patch Available

Incomplete Scheme Validation in Image Resizer · Advisory · octobercms/october · GitHub

Affected: v4.3.5.

https://github.com/octobercms/october/security/advisories/GHSA-2xmm-m4wv-3fjh

Vendor Advisories for CVE-2026-100909(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Affected Packages

(1 across 1 ecosystem)
Packagist(1)
PackageVulnerable rangeFixed inDependents
october/octoberv4.3.0, v4.3.1, v4.3.2, v4.3.44.3.5—

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 35× in last 7d / 35× 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. 2026-10-04 05:59 UTCGHSA enrichment
  2. 2026-10-03 18:47 UTCEG score recompute
  3. 2026-10-03 18:47 UTCGHSA enrichment
  4. 2026-10-03 14:25 UTCEPSS rescore
  5. 2026-10-03 07:34 UTCGHSA enrichment
  6. 2026-10-02 20:19 UTCEG score recompute
  7. 2026-10-02 20:19 UTCGHSA enrichment
  8. 2026-10-02 09:06 UTCGHSA enrichment
  9. 2026-10-01 21:55 UTCEG score recompute
  10. 2026-10-01 21:55 UTCGHSA enrichment
  11. 2026-10-01 19:49 UTCEPSS rescore
  12. 2026-10-01 10:41 UTCGHSA enrichment
  13. 2026-09-30 23:29 UTCEG score recompute
  14. 2026-09-30 23:29 UTCGHSA enrichment
  15. 2026-09-30 15:02 UTCEPSS rescore
  16. 2026-09-30 12:14 UTCGHSA enrichment
  17. 2026-09-30 01:02 UTCEG score recompute
  18. 2026-09-30 01:02 UTCGHSA enrichment
  19. 2026-09-29 15:20 UTCEPSS rescore
  20. 2026-09-29 13:51 UTCGHSA enrichment
  21. 2026-09-29 02:40 UTCEG score recompute
  22. 2026-09-29 02:40 UTCGHSA enrichment
  23. 2026-09-28 15:28 UTCEG score recompute
  24. 2026-09-28 15:28 UTCGHSA enrichment
  25. 2026-09-28 13:50 UTCEPSS rescore
Show 10 more
  1. 2026-09-28 13:29 UTCEG score recompute
  2. 2026-09-28 13:29 UTCGHSA enrichment
  3. 2026-09-28 13:29 UTCNVD updateCVSS v4 → 5.5
  4. 2026-09-28 12:52 UTCEG score recompute
  5. 2026-09-28 12:52 UTCGHSA enrichment
  6. 2026-09-28 12:52 UTCMITRE cvelistV5CVSS v4 → 6.9
  7. 2026-09-28 05:21 UTCEG score recompute
  8. 2026-09-28 05:21 UTCNVD updateCVSS v4 → 5.5
  9. 2026-09-28 04:47 UTCEG score recompute
  10. 2026-09-28 04:47 UTCMITRE cvelistV5first tracked

Related CVEs(same product + same CWE)

Frequently asked(5)

What is CVE-2026-100909?
CVE-2026-100909 is a high vulnerability published on September 28, 2026. A vulnerability was found in OctoberCMS up to 4.1.19/4.2.25/4.3.4. The impacted element is the function getSourcePathForResize of the file modules/system/classes/ResizeImages.php. The manipulation of the argument realSourcePath results in server-side request forgery. The attack may be performed…
When was CVE-2026-100909 disclosed?
CVE-2026-100909 was first published on September 28, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-100909 actively exploited?
CVE-2026-100909 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.3% probability of exploitation in the next 30 days (20th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-100909?
CVE-2026-100909 has a CVSS base score of 7.3 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
How do I remediate CVE-2026-100909?
A fix for CVE-2026-100909 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-100909 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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