CVE-2026-20122
CWE-648Published: February 25, 2026· Updated: Feb 27, 2026
Official Description
A vulnerability in the API of Cisco Catalyst SD-WAN Manager could allow an authenticated, remote attacker to overwrite arbitrary files on the local file system. To exploit this vulnerability, the attacker must have valid read-only credentials with API access on the affected system.
This vulnerability is due to improper file handling on the API interface of an affected system. An attacker could exploit this vulnerability by uploading a malicious file on the local file system. A successful exploit could allow the attacker to overwrite arbitrary files on the affected system and gain vmanage user privileges.
Technical Analysis
CVE-2026-20122 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.
Exploitation requires low privileges, which limits the exposure to scenarios where an attacker has already gained initial access.
CISA has added CVE-2026-20122 to the Known Exploited Vulnerabilities (KEV) catalog, confirming active exploitation in the wild. U.S. federal agencies are required to patch this within the mandated timeframe, and all organizations should treat remediation as urgent.
CVSS v3.1 Vector Breakdown
Affected Vendors & Products
Exploit & PoC Resources
News & Research Mentioning CVE-2026-20122
CISA has added eight new vulnerabilities to its Known Exploited Vulnerabilities (KEV) Catalog, based on evidence of active exploitation. CVE-2023-27351 PaperCut NG/MF Improper Authentication Vulnerability CVE-2024-27199 JetBrains TeamCity Relative Path Traversal Vulnerability CVE-2025-2749 Kentico Xperience Path Traversal Vulnerability CVE-2025-32975 Quest KACE Systems Management Appliance (SMA) Improper Authentication Vulnerability CVE-2025-48700 Synacor Zimbra Collaboration Suite (ZCS) Cross-site Scripting Vulnerability CVE-2026-20122 Cisco Catalyst SD-WAN Manager Incorrect Use of Privileged APIs Vulnerability CVE-2026-20128 Cisco Catalyst SD-WAN Manager Storing Passwords in a Recoverable Format Vulnerability CVE-2026-20133 Cisco Catalyst SD-WAN Ma [xlite_meta score:63 src:CISA Alerts xlite_fp:0b55e79970c47e4ece69ce1dd3660bb43f47c536c063390ae3b0b0034a186fa0]
Cisco has disclosed that two more vulnerabilities affecting Catalyst SD-WAN Manager (formerly SD-WAN vManage) have come under active exploitation in the wild. The vulnerabilities in question are listed below - CVE-2026-20122 (CVSS score: 7.1) - An arbitrary file overwrite vulnerability that could allow an authenticated, remote attacker to overwrite arbitrary files on the local file system. [xlite_meta score:50 src:The Hacker News xlite_fp:ac54efa927bcdc921f789eb032e6e8da0b33fc801870315e9eaabbd418ac0a7b]
The networking giant has added the recently patched CVE-2026-20128 and CVE-2026-20122 to the list of exploited vulnerabilities. The post Cisco Warns of More Catalyst SD-WAN Flaws Exploited in the Wild appeared first on SecurityWeek. [xlite_meta score:53 src:SecurityWeek xlite_fp:d89cd03c82cf45114274616a505954c09c8e01243e69caf7b9f7b85245ae7f6a]
All References (1)
Quick Facts
Known Threat Actors
Related CVEs (CWE-648)
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2026-20122 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts
- !CISA KEV: Federal agencies must patch per BOD 22-01 timeline
- !Active exploitation confirmed — treat as P1