- Critical 9.9
CVE-2026-57155
OPNsense is a FreeBSD based firewall and routing platform. Prior to version 26.1.11, the Firewall Alias GeoIP importer's process_zip() and process_gzip() paths in src/opnsense/scripts/filter/lib/alias/geoip.py use an unvalidated CSV country_code value to construct output filenames below /usr/local/share/GeoIP/alias. A user with Firewall Alias Edit privilege can configure an attacker-controlled GeoIP source URL and supply an archive whose country code traverses into another existing directory, causing attacker-controlled content to be written as root with an -IPv4 or -IPv6 suffix. A crafted ne…
Scores
The facts
- Published
- 15 October 2026
- Last changed
- 15 October 2026
- NVD status
- Deferred
- Severity
- Critical, CVSS 9.9 out of 10 (version 3.1)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H - Weakness
- Known exploited
- Not in the CISA Known Exploited Vulnerabilities catalogue in this build.
- EPSS
- 0.9% chance of exploitation activity in the next 30 days (percentile 58).
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