CVE-2026-100391

HIGHPre-NVD 8.28.2—
EchelonGraph scoreHIGH confidence

Score 8.2 from GitHub Security Advisory (severity: HIGH) published 2026-09-25. A secondary CVSS source baseline 8.2; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
Trending — 3 sources updated this week
8.2EG
EchelonGraph verdictPlan mitigationSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0.3%CVSS: 8.2Exploit: None knownExposed services: Not assessed

An upstream fix is merged but not yet released — mitigate (WAF / firewall / segmentation) until the release ships, then apply it.

MediaFlow Proxy through 2.4.9 contains a server-side request forgery vulnerability in the /proxy routes due to missing and incomplete destination validation in the d query parameter. Remote attackers can supply arbitrary internal URLs including loopback and cloud metadata endpoints to read full responses from the proxy server.

CVSS v3
8.2
EG Score
8.2HIGHhigh confidence
EG Risk
42
EG Risk 42/100CISA 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
Severity82% × 45%
Exploitation0% × 40%
Automatability30% × 15%
CISA SSVC: Track at low or medium mission impact; Track or Attend at high (mission-essential systems).
Action: An upstream fix is merged but not yet in a tagged release. 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 until it ships, then apply the release.
EPSS PROB
0.3%
EPSS %ILE
21st
KEV
Not listed

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

An upstream fix is merged but not yet in a tagged release. 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 until it ships, then apply the release.

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

September 25, 2026

Last Modified

September 30, 2026

Advisory Details (4)

Auto-updated Sep 25, 2026
Upstream fix merged — awaiting tagged release. Sources: github_commit.
generic

MediaFlow Proxy through 2.4.9 Server-Side Request Forgery via Incomplete Validation | Advisories | VulnCheck

https://www.vulncheck.com/advisories/mediaflow-proxy-through-2.4.9-server-side-request-forgery-via-incomplete-validation
generic

GitHub - mhdzumair/mediaflow-proxy: A high-performance proxy server for streaming media, supporting HTTP(S), HLS, and MPEG-DASH with real-time DRM decryption, acestream, xtreamcode proxy · GitHub

https://github.com/mhdzumair/mediaflow-proxy
generic

mediaflow-proxy/mediaflow_proxy/routes/proxy.py at 2.4.9 · mhdzumair/mediaflow-proxy · GitHub

https://github.com/mhdzumair/mediaflow-proxy/blob/2.4.9/mediaflow_proxy/routes/proxy.py#L532-L569
github_commit

commit 99f4af1153d4 (mhdzumair/mediaflow-proxy)

Fix landed in mhdzumair/mediaflow-proxy commit 99f4af1153d4 — awaiting tagged release

https://github.com/mhdzumair/mediaflow-proxy/commit/99f4af1153d4766420a098a232183cba1efdc560

Vendor Advisories for CVE-2026-100391(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 27× in last 7d / 39× 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. 2026-10-05 06:17 UTCEG score recompute
  2. 2026-10-05 06:17 UTCGHSA enrichment
  3. 2026-10-04 23:21 UTCEPSS rescore
  4. 2026-10-04 18:14 UTCGHSA enrichment
  5. 2026-10-04 06:11 UTCGHSA enrichment
  6. 2026-10-03 18:09 UTCEG score recompute
  7. 2026-10-03 18:09 UTCGHSA enrichment
  8. 2026-10-03 14:25 UTCEPSS rescore
  9. 2026-10-03 06:04 UTCGHSA enrichment
  10. 2026-10-02 18:01 UTCEG score recompute
  11. 2026-10-02 18:01 UTCGHSA enrichment
  12. 2026-10-02 05:59 UTCEG score recompute
  13. 2026-10-02 05:59 UTCGHSA enrichment
  14. 2026-10-01 19:49 UTCEPSS rescore
  15. 2026-10-01 17:56 UTCGHSA enrichment
  16. 2026-10-01 05:49 UTCGHSA enrichment
  17. 2026-09-30 17:47 UTCEG score recompute
  18. 2026-09-30 17:47 UTCGHSA enrichment
  19. 2026-09-30 15:02 UTCEPSS rescore
  20. 2026-09-30 11:51 UTCGHSA enrichment
  21. 2026-09-29 23:49 UTCEG score recompute
  22. 2026-09-29 23:49 UTCGHSA enrichment
  23. 2026-09-29 15:20 UTCEPSS rescore
  24. 2026-09-29 09:38 UTCGHSA enrichment
  25. 2026-09-28 21:34 UTCEG score recompute
Show 14 more
  1. 2026-09-28 21:34 UTCGHSA enrichment
  2. 2026-09-28 13:50 UTCEPSS rescore
  3. 2026-09-28 09:32 UTCGHSA enrichment
  4. 2026-09-27 21:29 UTCEG score recompute
  5. 2026-09-27 21:29 UTCGHSA enrichment
  6. 2026-09-27 09:25 UTCGHSA enrichment
  7. 2026-09-26 21:23 UTCEG score recompute
  8. 2026-09-26 21:23 UTCGHSA enrichment
  9. 2026-09-26 15:58 UTCEPSS rescore
  10. 2026-09-26 09:21 UTCEG score recompute
  11. 2026-09-26 09:21 UTCGHSA enrichment
  12. 2026-09-25 21:19 UTCEG score recompute
  13. 2026-09-25 20:24 UTCEG score recompute
  14. 2026-09-25 20:24 UTCMITRE cvelistV5first tracked

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-100391?
CVE-2026-100391 is a high vulnerability published on September 25, 2026. MediaFlow Proxy through 2.4.9 contains a server-side request forgery vulnerability in the /proxy routes due to missing and incomplete destination validation in the d query parameter. Remote attackers can supply arbitrary internal URLs including loopback and cloud metadata endpoints to read full…
When was CVE-2026-100391 disclosed?
CVE-2026-100391 was first published on September 25, 2026, with the most recent update on September 30, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-100391 actively exploited?
CVE-2026-100391 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.3% probability of exploitation in the next 30 days (21st percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-100391?
CVE-2026-100391 has a CVSS base score of 8.2 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
How do I remediate CVE-2026-100391?
An upstream fix for CVE-2026-100391 has been merged but is not yet in a tagged release. Until it ships, restrict network exposure of the affected system or apply the vendor's mitigation, then update to the release that contains the fix. The vendor advisories EchelonGraph has for CVE-2026-100391 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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