CVE-2026-56661

HIGHPre-NVD 7.57.5—
EchelonGraph scoreMEDIUM confidence

This high-severity CVE scores 7.5 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.3% (16th percentile of EPSS-scored CVEs). GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: epss, secondary
Trending — 3 sources updated this week
7.5EG
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: 7.5Exploit: None knownExposed services: Not assessed

A fix is available — apply it.

GetSimple CMS is a content management system (CMS), and GetSimple CMS CE is the community edition of that CMS. Prior to version 1.5, the update handler fetches a user-supplied URL with file_get_contents() after only format validation (FILTER_VALIDATE_URL) — there is no validation of the request destination. An attacker who can submit the form can make the server issue requests to arbitrary destinations, including internal-only services and cloud metadata endpoints (169.254.169.254). The fetched response body is written to a web-accessible file (/Tmpfile.zip) and is not deleted when the content is not a valid ZIP, turning this into a full-read SSRF: the attacker can retrieve the response of the internal request directly. This issue has been patched in version 1.5.

CVSS v3
7.5
EG Score
7.5HIGHmedium confidence
EG Risk
38
EG Risk 38/100CISA 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
Severity75% × 45%
Exploitation0% × 40%
Automatability30% × 15%
CISA SSVC: Track at low or medium mission impact; Track or 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
16th
KEV
Not listed

CISA SSVCTrack at low or medium mission impact; Track or 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 none (no KEV listing, exploit record or EPSS ≥ 50%) · Automatable unknown (not published for this CVE) · Technical impact partial (CVSS below 9.0). 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

October 1, 2026

Last Modified

October 1, 2026

Advisory Details (1)

Auto-updated Oct 1, 2026
🔬 Proof of concept available. Patch available. Sources: github.
github Patch Available🟡 PoC Available

Server-Side Request Forgery in the UpdateCE update endpoint · Advisory · GetSimpleCMS-CE/GetSimpleCMS-CE · GitHub

https://github.com/GetSimpleCMS-CE/GetSimpleCMS-CE/security/advisories/GHSA-r7v8-mx29-5q8h

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 7× in last 7d / 7× 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 00:33 UTCEG score recompute
  2. 2026-10-03 14:26 UTCEPSS rescore
  3. 2026-10-02 22:17 UTCEG score recompute
  4. 2026-10-02 17:56 UTCEPSS rescore
  5. 2026-10-01 20:29 UTCEG score recompute
  6. 2026-10-01 19:46 UTCEG score recompute
  7. 2026-10-01 19:45 UTCMITRE cvelistV5first tracked

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Frequently asked(5)

What is CVE-2026-56661?
CVE-2026-56661 is a high vulnerability published on October 1, 2026. GetSimple CMS is a content management system (CMS), and GetSimple CMS CE is the community edition of that CMS. Prior to version 1.5, the update handler fetches a user-supplied URL with filegetcontents() after only format validation (FILTERVALIDATEURL) — there is no validation of the request…
When was CVE-2026-56661 disclosed?
CVE-2026-56661 was first published 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-2026-56661 actively exploited?
CVE-2026-56661 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.3% probability of exploitation in the next 30 days (16th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-56661?
CVE-2026-56661 has a CVSS base score of 7.5 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
How do I remediate CVE-2026-56661?
A fix for CVE-2026-56661 is available: update to the fixed version the vendor names in its advisory.

Dependency Blast Radius

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