Skip to main content
CRITICAL

CVE-2026-57155

CVSS v3

9.9

CRITICAL

EPSS Score

0.9 %

exploit probability, as of 2026-10-16

CISA KEV

No

known exploited

Exploitation

—

SSVC status

Get an alert for each new CVE published for the software you run. Set up CVE Watch Free account · no credit card

Affected and fixed versions

Neither OSV.dev nor the vendor advisories we read list affected versions for CVE-2026-57155 yet.

Full record on NVD

Description

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 newsyslog fragment and oversized log file can use the default hourly root cron job to execute commands as root, resulting in complete firewall compromise. This issue is fixed in version 26.1.11.

Technical details

CVSS v3 Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
Published
2026-10-15
Last Modified
2026-10-15

Frequently asked questions

What is 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 newsyslog fragment and oversized log file can use the default hourly root cron job to execute commands as root, resulting in complete firewall compromise. This issue is fixed in version 26.1.11.

Is CVE-2026-57155 actively exploited?

Active exploitation of CVE-2026-57155 has not been confirmed. Its EPSS score was 0.9% on 2026-10-16, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2026-57155?

CVE-2026-57155 has a CVSS v3 base score of 9.9 (CRITICAL severity), with vector string CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H.

Hear about the next vulnerability in your software

CVE Watch matches each new CVE to the vendors and products you list (vendor and product, not the version) and puts it in your alerts with its KEV and EPSS status.

Get alerts for this productCISA KEV additions, October 2026Search CVEs

Already have an account? Open CVE WatchNo credit card required · 50 free checks/month · Free API key

Go further

Related vulnerabilities

Same product first, then the same vendor advisory and the same publication week.

Back to CVE Database