CVE-2026-76504

CRITICALPre-NVD 9.89.8—
EchelonGraph scoreHIGH confidence

Score elevated to 9.8 because this CVE is listed on the CISA Known Exploited Vulnerabilities catalog (added 2026-09-30), indicating real-world exploitation has been confirmed by US federal agencies. A secondary CVSS source baseline 9.8 retained for reference (NVD's own analysis pending). Confidence: HIGH.

Triggered by: CISA KEV (actively exploited)
Sources: cisa_kev, epss, ghsa, secondary
Trending — KEV-added this weekExploited in the wild
9.8EG
EchelonGraph verdictPatch nowTreat as an emergency — this is being exploited.
  • Actively exploited in the wild (CISA-KEV)
CISA-KEV: ExploitedEPSS PROB: 1.6%CVSS: 9.8Exploit: cisa kev · ssvc active · public exploitExposed services: Not assessed

A fix is available — apply it.

A vulnerability in the API session-based authentication management of Cisco Catalyst SD-WAN Manager could allow an unauthenticated, remote attacker to access an affected system with privileges of the admin user. This vulnerability is due to improper handling of URI encoding in an HTTP request, which allows the request to bypass an authentication rule that is intended to restrict access to a specific API endpoint. An attacker could exploit this vulnerability by sending a crafted HTTP request to the API of the affected system. A successful exploit could allow the attacker to bypass authentication and gain access to the API as the admin user.

CVSS v3
9.8
EG Score
9.8CRITICALhigh confidence
EG Risk
99
EG Risk 99/100CISA 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
Severity98% × 45%
Exploitation100% × 40%
Automatability100% × 15%
CISA SSVC: Attend at low mission impact; Act at medium or high.
Action: A fix is available. Apply it sooner than your standard update timelines at low mission impact and as soon as possible at medium or high.
EPSS PROB
1.6%
EPSS %ILE
74th
KEV
⚠ Exploited

CISA SSVCAttend at low mission impact; Act at medium or high.

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

Exploitation active (CISA Vulnrichment) · Automatable yes (CISA Vulnrichment) · Technical impact total (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 3, 2026

Advisory Details (2)

Auto-updated Oct 3, 2026
⚠️ Active exploitation confirmed. Patch available. Sources: cisa.
cisa Patch Available🔴 Active Exploitation

Known Exploited Vulnerabilities Catalog | CISA

Known Exploited Vulnerabilities Catalog | CISA. Listed in CISA Known Exploited Vulnerabilities catalog.

https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-76504
generic

Cisco Catalyst SD-WAN Manager API Authentication Bypass Vulnerability

https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sdwan-webauth-xr8beuuU

Vendor Advisories for CVE-2026-76504(2)

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 44× in last 7d / 44× 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 06:54 UTCGHSA enrichment
  2. 2026-10-04 02:32 UTCGHSA enrichment
  3. 2026-10-03 22:11 UTCGHSA enrichment
  4. 2026-10-03 17:49 UTCEG score recompute
  5. 2026-10-03 17:49 UTCGHSA enrichment
  6. 2026-10-03 14:26 UTCEPSS rescore
  7. 2026-10-03 13:27 UTCGHSA enrichment
  8. 2026-10-03 09:04 UTCGHSA enrichment
  9. 2026-10-03 04:41 UTCEG score recompute
  10. 2026-10-03 04:41 UTCGHSA enrichment
  11. 2026-10-03 00:19 UTCEG score recompute
  12. 2026-10-03 00:19 UTCGHSA enrichment
  13. 2026-10-02 23:32 UTCEG score recompute
  14. 2026-10-02 23:32 UTCGHSA enrichment
  15. 2026-10-02 19:46 UTCEG score recompute
  16. 2026-10-02 19:46 UTCGHSA enrichment
  17. 2026-10-02 15:23 UTCGHSA enrichment
  18. 2026-10-02 10:59 UTCGHSA enrichment
  19. 2026-10-02 06:36 UTCGHSA enrichment
  20. 2026-10-02 02:13 UTCGHSA enrichment
  21. 2026-10-01 21:49 UTCEG score recompute
  22. 2026-10-01 21:48 UTCGHSA enrichment
  23. 2026-10-01 19:50 UTCEPSS rescore
  24. 2026-10-01 17:25 UTCGHSA enrichment
  25. 2026-10-01 13:03 UTCGHSA enrichment
Show 19 more
  1. 2026-10-01 08:41 UTCGHSA enrichment
  2. 2026-10-01 04:19 UTCEG score recompute
  3. 2026-10-01 04:19 UTCGHSA enrichment
  4. 2026-10-01 04:06 UTCEG score recompute
  5. 2026-10-01 04:06 UTCGHSA enrichment
  6. 2026-10-01 03:09 UTCGHSA enrichment
  7. 2026-09-30 22:47 UTCEG score recompute
  8. 2026-09-30 22:47 UTCGHSA enrichment
  9. 2026-09-30 20:06 UTCEG score recompute
  10. 2026-09-30 20:05 UTCGHSA enrichment
  11. 2026-09-30 19:05 UTCGHSA enrichment
  12. 2026-09-30 18:25 UTCEG score recompute
  13. 2026-09-30 18:25 UTCGHSA enrichment
  14. 2026-09-30 17:41 UTCEG score recompute
  15. 2026-09-30 17:41 UTCGHSA enrichment
  16. 2026-09-30 17:24 UTCCISA KEV update
  17. 2026-09-30 13:18 UTCEG score recompute
  18. 2026-09-30 13:12 UTCEG score recompute
  19. 2026-09-30 13:11 UTCMITRE cvelistV5first tracked

Publicly available exploits

(1 reference)

Working exploit code is in the public domain (1 GitHub PoC). Defenders should treat patch urgency accordingly — public PoCs typically lead to mass-exploitation within 24-72 hours.

  • GitHub PoCShadowForge-Cyber/CVE-2026-76504-Proof-of-concept
    First seen Sep 30, 2026

    EUVD-2026-89950 Improper Handling of URL Encoding (Hex Encoding) (CWE-177)

    Open source ↗

Related CVEs(same CWE)

Frequently asked(6)

What is CVE-2026-76504?
CVE-2026-76504 is a critical vulnerability published on September 30, 2026. A vulnerability in the API session-based authentication management of Cisco Catalyst SD-WAN Manager could allow an unauthenticated, remote attacker to access an affected system with privileges of the admin user. This vulnerability is due to improper handling of URI encoding in an HTTP request,…
When was CVE-2026-76504 disclosed?
CVE-2026-76504 was first published on September 30, 2026, with the most recent update on October 3, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-76504 actively exploited?
Yes. CISA added CVE-2026-76504 to the Known Exploited Vulnerabilities catalog on September 30, 2026, affecting Cisco Catalyst SD-WAN Manager. KEV listing indicates confirmed exploitation in the wild; this CVE warrants immediate attention. A fix is available. Apply it.
What is the CVSS score of CVE-2026-76504?
CVE-2026-76504 has a CVSS base score of 9.8 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
Which products are affected by CVE-2026-76504?
CVE-2026-76504 affects Cisco Catalyst SD-WAN Manager.
How do I remediate CVE-2026-76504?
A fix for CVE-2026-76504 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-76504 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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