CVE-2026-119423: OPNsense core before 26.7.8 Lockout IP Planting via WebGUI Login Username
Noroxi assessment
Priority: Monitor (action score 27/100)
- The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
- Probability of exploitation in the next 30 days: 0.37% (FIRST EPSS).
- Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
- According to CISA the attack is automatable: targets can be found by mass scanning.
- Fixed version: opnsense core 26.7.8.
Low priority for now. Upgrade to opnsense core 26.7.8 or later.
Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it
Primary sources: NVD · CVE.org · FIRST EPSS
OPNsense core before 26.7.8 contains a log injection vulnerability that allows unauthenticated attackers to plant victim IP addresses in the lockout_handler by submitting crafted WebGUI login usernames. Attackers can submit usernames like 'Invalid user <victim-ip>' repeatedly to add the victim to the sshlockout table, blocking SSH and WebGUI access and killing its pf states.
- Published
- Oct 30, 2026
- Updated
- Nov 4, 2026
- EPSS
- 0.3% · 32th percentile
- CWE
- CWE-117
Report tools
Action score
27
Low priority for now.
- CVSS
- 27 / 40 · 6.9 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · 0.3%
CISA SSVC decision
- Exploitation
- none
- Automatable
- yes
- Technical impact
- partial
Vulnrichment: CISA's decision-tree inputs.
CNA vs NVD score
- NVD
- —
- CNA · VulnCheck
- 6.9
- NVD has not scored this yet; the score shown is the CNA’s.
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.
Get told when this record changes
- Not in KEV: no record of exploitation in the wild
- No public exploit code on record
- A fix has been released
If any of these changes, we'll tell you in the daily email digest.
Is your version affected? Check itNoroxi analysis
What does it mean in your environment?
The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.
We use this product, ask for helpAffected systems
Is your version affected?
Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.
—
Versions reported by the vendor
Affected version ranges reported by the assigning authority (VulnCheck). Independent of NVD's CPE analysis and usually ahead of it.
opnsense core
- before 26.7.8affected · semver
Same product
opnsense: all recordsOther highest-scoring records for the same primary product.
- CVE-2026-57155OPNsense: Root RCE via Arbitrary File Write in GeoIP Alias Importer39Monitor
- CVE-2026-53581ntp: write path traversal36Monitor
- CVE-2026-119409OPNsense before 26.7.8 Root Command Injection via Firmware Mirror Setting35Monitor
Published before and after this one in the same product
- ← EarlierCVE-2026-63442Oct 15, 2026 · OPNsense: Log Forgery via Login Username CRLF in WebGUI Authentication → Pf Table IP Blocking32Monitor
- ← EarlierCVE-2026-71490Oct 15, 2026 · OPNsense: Direct comma-separated user privileges bypass OPNsense MVC read-only write protection28Monitor
- Later →CVE-2026-119424Oct 30, 2026 · OPNsense before 26.7.8 Wireless WPA Configuration Line Injection via Identity24Monitor
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
| Product / package | Fixed version | Source |
|---|---|---|
| opnsense core | 26.7.8 | Vendor (CNA) |
Exploit status
No known public exploit
No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
- Published
- Fix recordedsame day
- TodayNov 13, 2026+14 d
FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
- Abraxas Labsfinder
- Ad Schellevisremediation developer
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
- CVE-2026-6344215 days apartOPNsense: Log Forgery via Login Username CRLF in WebGUI Authentication → Pf Table IP Blocking32Monitor
Not on record for this CVE: public bounty program.
Technical details
Attack conditions
- Anyone who can reach it over the internet can trigger it.
- No account or password is required.
- No user action is required.
- No special conditions are required; it is repeatable.
If successful
- Confidentiality
- Integrity
- Availability
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- None
- Scope
- X
Weakness class (CWE)
CWE-117 · Improper Output Neutralization for LogsCVSS vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
nvd-secondary
Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
Attack patterns (CAPEC)
Change log
- SSVC exploitation— → none
- Exploit maturity— → none
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
Show all references (7 more)Show less
- github.com/opnsense/core
- github.com/opnsense/core/blob/26.7.7/src/opnsense/mvc/app/library/OPNsense/Auth/AuthenticationFactory.php#L232
- github.com/opnsense/core/blob/26.7.7/src/opnsense/scripts/syslog/lockout_handler#L70
- github.com/opnsense/core/commit/14f8f7dd1d5f06522d60794a7beeac7adb9eca68
- github.com/opnsense/core/commit/2076f2c195bf9537ec220f0e5d6aff998f057410
- github.com/opnsense/core/security/advisories/GHSA-2v2x-m4j7-76pv
- www.vulncheck.com/advisories/opnsense-core-before-26.7.8-lockout-ip-planting-via-webgui-login-username
Vendor advisories and official records. Exploit/PoC links are deliberately left out.