CVE-2021-20090
Exploited in the wild. In CISA KEV since 2021‑11‑03. A vendor fix is available.
What to do
The vendor has published a fix. Version details are below where the sources state them.
- n/a Buffalo WSR-2533DHPL2, Buffalo WSR-2533DHP3Affected: WSR-2533DHPL2 <=1.02, WSR-2533DHP3 <= 1.24Upgrade to: not statedStated by: CVE record
- Buffalo Wsr-2533dhpl2-bk FirmwareAffected: ≤ 1.02Upgrade to: after 1.02Stated by: NVD
- Buffalo Wsr-2533dhp3-bk FirmwareAffected: ≤ 1.24Upgrade to: after 1.24Stated by: NVD
- Buffalo Technology Buffalo wsr-2533dhpl2-bkAffected: до 1.02Upgrade to: not statedStated by: BDU
- Buffalo Technology Buffalo wsr-2533dhp3-bkAffected: до 1.24Upgrade to: not statedStated by: BDU
Versions as the sources state them. 4 more products have version data. Full version matrix after sign-in
Coverage timeline
0 publishersAdded to CISA KEV catalog
Sourced from public security reporting — each date is when it was published, not when it happened.
What it is
From the CVE record
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.
In plain language
No plain-language summary for this CVE yet.
Exploitation
Where each signal puts this CVE on the scale from published to confirmed exploited.
- CISA KEV
Listed as exploited in the wild since 2021-11-03.
US federal agencies must remediate by 2021-11-17.
Apply updates per vendor instructions.
- Public exploits
No public exploit or proof of concept found in the sources we track.
- EPSS
100% chance of exploitation activity in the next 30 days, which ranks it in the 99th percentile of scored CVEs.
Exploit Prediction Scoring System, FIRST.org. A probability, not a confirmation.
Lifecycle
8 events over 1883 days, from the signal feeds we watch.
- OpenVAS check added
- Nuclei check added
- Patch availablerecord updated
- Added to CISA KEV
- Publishedweakness classified, att&ck mapped
Affected products
And 1 more affected product. See all after sign-in
Technical detail
CVSS 3.1 vector
Open in the CVSS calculatorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Scored 9.8 by NVD.
How it is reached
- Attack Vector NetworkExploitable remotely over the network without any special conditions
- Attack Complexity LowNo special conditions — the attack can be reliably reproduced
- Privileges Required NoneNo authentication required — anyone can exploit this
- User Interaction NoneNo user interaction needed — fully automated exploitation
Scope
- Scope UnchangedImpact is limited to the vulnerable component itself
Impact if exploited
- Confidentiality HighTotal information disclosure — all data in the component is compromised
- Integrity HighTotal loss of integrity — attacker can modify any data in the component
- Availability HighTotal denial of service — the component is completely unavailable
Weaknesses
ATT&CK techniques
Mapped from the weaknesses above (CWE to ATT&CK), not observed in attacks.
Sources
References in the record
- tenable.com/security/research/tra-2021-13&
- kb.cert.org/vuls/id/914124&
- nvd.nist.gov/vuln/detail/CVE-2021-20090
And 4 more references. See all after sign-in
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