CVE-2026-76504

criticalpriority · act · 90OT risk · criticalKEV · exploitedEPSS 0.389 · 99 %ileexploit · PoCDENLRUUS
grimoire priorityP0 · Act now
Exploitable?
Yes · in the wild
CISA KEV · 3 exploits · PoC
Likely / severe?
38.9% (99th) EPSS
CVSS 9.8 · critical
Is it mine?
787 products
Check your exposure
Who says so?
4 sources
fstec_bdu · cert_bund · cisco_csaf · ncsc_nl

added 2026-09-30remediate by 2026-10-03

required action Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.

EPSS · scored 2026-10-27

Cisco Catalyst SD-WAN Manager Hex Encoding Vulnerability

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.

01

remediations

Vendor fix, mitigation, or workaround guidance, as published by each source.

A vendor fix is available.

02

cvss

Technical severity, 0–10. One row per scoring source.

9.8
010

base score 0–10 · higher = more severe · hover a vector to decode

v3.19.8criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hprimary · psirt@cisco.com USexploitability 3.9 · impact 5.9
v3.19.8criticalAV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hsecondary · FSTEC (BDU) RU
v3.19.8criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:Hsecondary · CVSS-BT (t0sche)
v3.19.8criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hsecondary · NCSC-NL NL
v3.19.8criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hsecondary · Cisco PSIRT US
03

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: active · Automatable: yes · Technical Impact: totalcoordinatorcisa_ssvcUS
04

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-177USCWE-177USCWE-177US
05

exploits (3)

Public proof-of-concept and weaponised exploit code.

06

affected products (787)

Products and version ranges known to be affected.

showing 20 of 787
07

advisories (3)

Vendor and ecosystem advisories describing this.

  • NCSC-2026-0395Kwetsbaarheid verholpen in Cisco Catalyst SD-WAN ManagerNL2026-09-30csaf · ncsc_nlNL

    Cisco heeft een kwetsbaarheid verholpen in Cisco Catalyst SD-WAN Manager.

  • WID-SEC-W-2026-3681Cisco Catalyst SD-WAN Manager: Schwachstelle ermöglicht Erlangen von AdministratorrechtenDeutsch2026-09-30csaf · cert_bundDE

    Ein entfernter, anonymer Angreifer kann eine Schwachstelle in Cisco Catalyst SD-WAN Manager ausnutzen, um die Authentifizierung zu umgehen und Administratorrechte zu erlangen.

  • cisco-sa-sdwan-webauth-xr8beuuUCisco Catalyst SD-WAN Manager API Authentication Bypass Vulnerability2026-09-30csaf · cisco_csafUS

    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. Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability. Live Protect Shield Cisco has released a Live Protect shield for CVE-2026-76504 to provide temporary security coverage to allow time for software upgrade planning, including preserving any information that customers may require for governance or compliance purposes. This shield offers only temporary partial protection. The only way to remediate this vulnerability is to upgrade to the first fixed software release, as noted in the Fixed Releases ["#fs"] section of this advisory. Cisco strongly recommends prioritizing system upgrades and scheduling them as soon as possible to ensure remediation. Before deploying the shield, read the following information: Side Effects/Limitation: If this shield is applied A legitimate user with URI encoding might not be able to login to SDWAN Manager. For more information about Live Protect for Cisco Catalyst SD-WAN, see https://www.cisco.com/c/en/us/td/docs/routers/sdwan/26x-later/network-monitoring/network-monitoring-guide/live-protect-for-cisco-catalyst-sd-wan.html ["https://www.cisco.com/c/en/us/td/docs/routers/sdwan/26x-later/network-monitoring/network-monitoring-guide/live-protect-for-cisco-catalyst-sd-wan.html"].

08

also known as (2)

Other names and identifiers for this entity.

09

sources

Which sources assert this record, and when.

fstec_bducert_bundcisco_csafncsc_nlNVDCVE.orgMITRE
published 2026-09-30modified 2026-10-03
10

references (2) nvd

External citations — patches, advisories, analysis.

scry

Attackers weaponise vulnerabilities like this against internet-exposed services. See what is exposed on your perimeter with a free passive scan.

Free scan