Security readout for executives and security teams
Plain-English summary
OPNsense 19.1 has a reflected cross-site scripting issue in a proxy endpoint. An unauthenticated attacker could trick a user into interacting with a crafted request, causing script to run in that user’s browser. Business impact is mainly session, data, or administrative action risk if an administrator is targeted.
Executive priority
Prioritize remediation for OPNsense 19.1 systems used by administrators or exposed beyond trusted networks. This is not rated critical, but public exploit information and the firewall-management context justify timely patching and exposure reduction.
Technical view
CVE-2019-25376 is CWE-79 reflected XSS in OPNsense 19.1 involving the ignoreLogACL parameter on a proxy endpoint. CVSS 3.1 is 6.1, network exploitable, low complexity, no privileges required, but user interaction is required. Scope is changed with low confidentiality and integrity impact, no availability impact.
Likely exposure
Exposure is likely limited to organizations running OPNsense 19.1, especially where the affected proxy endpoint is reachable by users or administrators. Internet exposure increases phishing risk, but successful exploitation still depends on user interaction.
Exploitation context
A public ExploitDB reference exists, so proof-of-concept information is publicly available. The provided sources do not show CISA KEV listing or confirmed active exploitation. Treat this as a realistic phishing or admin-targeting risk, not a confirmed mass-exploitation event.
Researcher notes
Evidence identifies OPNsense 19.1, reflected XSS, ignoreLogACL, and a proxy endpoint. Patch details should be confirmed from OPNsense release materials because the provided bundle names the 19.1.1 announcement but does not include full fix text. No active exploitation evidence is provided.
Mitigation direction
- Identify any OPNsense 19.1 systems.
- Review OPNsense 19.1.1 release guidance and apply the vendor-supported fix path.
- Upgrade affected systems to a supported, fixed OPNsense release.
- Restrict management and proxy-related access to trusted networks where feasible.
- Warn administrators not to interact with untrusted links or submitted requests.
Validation and detection
- Confirm installed OPNsense versions across firewalls and appliances.
- Check whether any system remains on OPNsense 19.1.
- Review access logs for unusual ignoreLogACL parameter activity.
- Verify vendor update history against the OPNsense 19.1.1 announcement.
- Document whether the proxy endpoint is reachable by untrusted users.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-79: User-session and phishing behavior lookup
Client-side and session-facing weaknesses should be reviewed alongside initial-access and user-execution behaviors. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCVE-2019-25376 mapping review
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Open ATT&CK lookup- Severity
- Medium
- CVSS
- 6.1 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N2.82.7Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
6.1MediumVector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Source materials
- CVE List V5 sourceCVE List V5
- ExploitDB-46351CVE reference · exploit
- OPNsense Official WebsiteCVE reference · product
- OPNsense 19.1.1 Release AnnouncementCVE reference · patch
- VulnCheck Advisory: OPNsense 19.1 Reflected XSS via proxy endpointCVE reference · third-party-advisory
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.