A vulnerability in the API user authentication of Cisco Catalyst SD-WAN Manager could allow an unauthenticated, remote attacker to gain access to an affected system as a user who has the netadmin role. The vulnerability is due to improper authentication for requests that are sent to the API. An attacker could exploit this vulnerability by sending a crafted request to the API of an affected system. A successful exploit could allow the attacker to execute commands with the privileges of the netadmin role. Note: Cisco Catalyst SD-WAN Manager releases 20.18 and later are not affected by this vulnerability.
CVE-2026-20129
CRITICALPre-NVD 9.89.8—Trending — 3 sources updated this week
EchelonGraph scoreMEDIUM confidence
Score 9.8 from GitHub Security Advisory (severity: CRITICAL) published 2026-02-25. the CNA's CVSS baseline 9.8; sources differ by 0.0.
Triggered by: GitHub Security Advisory CVSS
Sources: cna:cisco, ghsa
9.8EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
- High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 1%CVSS: 9.8Exploit: None knownExposed: 0
No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.
- CVSS v3
- 9.8
- EG Score
- 9.8(medium)
- EG Risk
- 59(Track)EG Risk 59/100SSVC: Track
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 computedSeverity98% × 45%Exploitation0% × 40%Automatability100% × 15%Action: Routine — remediate on your standard cadence. - EPSS PROB
- 1%
- EPSS %ILE
- 50%
- KEV
- Not listed
Published
February 25, 2026
Last Modified
June 17, 2026
Advisory Details (1)
Auto-updated Jul 27, 2026🔬 Proof of concept available. No patch confirmed yet.
generic🟡 PoC Available
Cisco Catalyst SD-WAN Vulnerabilities
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sdwan-authbp-qwCX8D4vVendor Advisories for CVE-2026-20129(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 3× in last 7d / 3× 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.
- 2026-07-27 14:13 UTCEPSS rescore
- 2026-07-27 12:55 UTCEG score recompute
- 2026-07-27 12:55 UTCGHSA enrichment
Related CVEs(same CWE)
Same CWE
10 shownCWE-287
Frequently asked(5)
What is CVE-2026-20129?
CVE-2026-20129 is a critical vulnerability published on February 25, 2026. A vulnerability in the API user authentication of Cisco Catalyst SD-WAN Manager could allow an unauthenticated, remote attacker to gain access to an affected system as a user who has the netadmin role. The vulnerability is due to improper authentication for requests that are sent to the API.…
When was CVE-2026-20129 disclosed?
CVE-2026-20129 was first published in the National Vulnerability Database on February 25, 2026, with the most recent update on June 17, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-20129 actively exploited?
CVE-2026-20129 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 1% probability of exploitation in the next 30 days, which ranks it in the top 50.0% of all scored CVEs.
What is the CVSS score of CVE-2026-20129?
CVE-2026-20129 has a CVSS v3 base score of 9.8 (NVD).
How do I remediate CVE-2026-20129?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-20129, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.
Dependency Blast Radius
Explore the affected products and dependency analysis for CVE-2026-20129
Is Your Infrastructure Affected by CVE-2026-20129?
EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.