CVE-2021-20090
Published on April 29, 2021
A path traversal vulnerability in the web interfaces of Buffalo WSR-2533DHPL2 firmware version <= 1.02 and WSR-2533DHP3 firmware version <= 1.24 could allow unauthenticated remote attackers to bypass authentication.
Known Exploited Vulnerability
This Arcadyan Buffalo Firmware Multiple Versions Path Traversal vulnerability is part of CISA's list of Known Exploited Vulnerabilities. A path traversal vulnerability in Arcadyan firmware could allow unauthenticated remote attackers to bypass authentication. It impacts many routers.
The following remediation steps are recommended / required by November 17, 2021: Apply updates per vendor instructions.
Vulnerability Analysis
CVE-2021-20090 is exploitable with network access, and does not require authorization privileges or user interaction. This vulnerability is considered to have a low attack complexity. This vulnerability is known to be actively exploited by threat actors in an automatable fashion. The potential impact of an exploit of this vulnerability is considered to be critical as this vulnerability has a high impact to the confidentiality, integrity and availability of this component.
Weakness Type
What is a Directory traversal Vulnerability?
The software uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the software does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory.
CVE-2021-20090 has been classified to as a Directory traversal vulnerability or weakness.
Exploit Probability
EPSS (Exploit Prediction Scoring System) scores estimate the probability that a vulnerability will be exploited in the wild within the next 30 days. The percentile shows you how this score compares to all other vulnerabilities.