CVE-2023-22915
No known exploitation. EPSS puts it in the 63rd percentile. A vendor fix is available.
What to do
The vendor has published a fix. Version details are below where the sources state them.
What it is
From the CVE record
A buffer overflow vulnerability in the “fbwifi_forward.cgi” CGI program of Zyxel USG FLEX series firmware versions 4.50 through 5.35, USG FLEX 50(W) firmware versions 4.30 through 5.35, USG20(W)-VPN firmware versions 4.30 through 5.35, and VPN series firmware versions 4.30 through 5.35, which could allow a remote unauthenticated attacker to cause DoS conditions by sending a crafted HTTP request if the Facebook WiFi function were enabled on an affected device.
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
Not in the catalog. CISA has not confirmed exploitation.
- Public exploits
No public exploit or proof of concept found in the sources we track.
- EPSS
1.1% chance of exploitation activity in the next 30 days, which ranks it in the 63rd percentile of scored CVEs.
Exploit Prediction Scoring System, FIRST.org. A probability, not a confirmation.
Lifecycle
6 events over 1158 days, from the signal feeds we watch.
- OpenVAS check added
- Patch availablerecord updated
- Publishedweakness classified, att&ck mapped
Affected products
- USG FLEX series firmwareNetworking Infrastructure
- USG FLEX 50(W) firmwareNetworking Infrastructure
- USG20(W)-VPN firmwareNetworking Infrastructure
- VPN series firmwareNetworking Infrastructure
- USG FLEXNetworking Infrastructure
- VPNNetworking Infrastructure
- USG FLEX 50(W)Networking Infrastructure
- USG 20(W)-VPNNetworking Infrastructure
And 12 more affected products. 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:N/I:N/A:H
Scored 7.5 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 NoneNo confidentiality impact
- Integrity NoneNo integrity impact
- 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.
- Initial AccessT1190Exploit Public-Facing Applicationhigh confidence
- Privilege EscalationT1068Exploitation for Privilege Escalationhigh confidence
Sources
References in the record
- zyxel.com/global/en/support/security-advisories/zyxel-security-advisory-for-multiple-vulnerabilities-of-firewalls-and-aps
- ptsecurity.com/ru-ru/about/news/positive-technologies-pomogla-zakryt-uyazvimosti-v-mezhsetevyh-ehkranah-i-tochkah-dostupa-zyxel/&
- zyxel.com/global/en/support/security-advisories/zyxel-security-advisory-for-multiple-vulnerabilities-of-firewalls-and-aps&
And 2 more references. See all after sign-in
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We'll flag the next CVE, public exploit or patch for USG FLEX Series Firmware, not every advisory.
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