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TI-2026-74827 Aliases CVE-2026-71490

OPNsense core lets users bypass read-only configuration protection

Priority MEDIUM 64CWE-863Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Security bypass
Confidentiality · integrity · availability
None · High · Low
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-863.

Summary

OPNsense core before 26.1.11 mishandles user privileges assigned directly as comma-separated values, so the read-only check is not applied. A user directly assigned both a component write privilege and user-config-readonly can bypass the restriction and persist configuration changes through MVC APIs protected by throwReadOnly(). Group privileges are not affected. A remote user with low privileges can exploit this (CWE-863).

Written with Claude Haiku 5.5 from the sources below · 2026-10-28

Description from the CNA

OPNsense is a FreeBSD based firewall and routing platform. Prior to 26.1.11, OPNsense\Core\ACL::hasPrivilege() appends a directly assigned comma-separated <priv> value as one string and then uses an exact comparison when checking user-config-readonly. A user directly assigned both a component write privilege and user-config-readonly can therefore be treated as lacking the read-only restriction, and MVC APIs protected by throwReadOnly() can persist configuration changes for that component. Group privileges are not affected by the same parser flaw because the group path already splits comma-separated values. This issue is fixed in version 26.1.11.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.0038 32nd percentileScored 2026-11-07
Fix Fixed core (opnsense): 26.1.11

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
opnsensecorebefore 26.1.1126.1.11Patch availableCNA
  • core Vendoropnsense Affected before 26.1.11 Fixed in 26.1.11 Patch available CNA

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPEVersionsRoleVendor
cpe:2.3:a:opnsense:opnsense:*:*:*:*:*:*:*:*——opnsense
  • cpe:2.3:a:opnsense:opnsense:*:*:*:*:*:*:*:* Versions — — ·opnsense

Remediation

Upgrade OPNsense core to version 26.1.11, which fixes this issue.

Written with Claude Haiku 5.5 from the sources below · 2026-10-28

  • Fix · CNA core (opnsense) Fixed in 26.1.11

Timeline

  1. 2026-10-16 Threatist record created from CVE-2026-71490

References

Other 4

  • TI-2023-20247 A command injection vulnerability in the component /api/cron/settings/setJob/ of OPNsense… CVSS 3.1CRITICAL 9.8
  • TI-2023-20243 Insecure permissions in the configuration directory (/conf/) of OPNsense Community… CVSS 3.1CRITICAL 9.8
  • TI-2023-20240 A command injection vulnerability in the component diag_backup.php of OPNsense Community… CVSS 3.1CRITICAL 9.8
  • TI-2023-11947 DECISO OPNsense 23.1 does not impose rate limits for authentication, allowing attackers… CVSS 3.1CRITICAL 9.8
  • TI-2026-74819 Path traversal in OPNsense GeoIP importer allows root code execution CVSS 3.1CRITICAL 9.9
  • TI-2023-20246 /ui/cron/item/open in the Cron component of OPNsense Community Edition before 23.7 and… CVSS 3.1CRITICAL 9.6
See all 54 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences