Security readout for executives and security teams
Plain-English summary
Older versions of Nagios XI, a popular IT monitoring platform, contain a flaw that lets a logged-in user plant malicious code inside two reporting screens. When another user views those reports, the code runs in their browser, potentially hijacking their session or stealing data shown in the monitoring console.
Executive priority
Schedule a routine patch cycle. This is a moderate-severity stored XSS that needs an authenticated user to exploit and is not known to be actively attacked, but Nagios XI often holds privileged visibility into infrastructure, so delaying the upgrade leaves administrator sessions at avoidable risk.
Technical view
Nagios XI prior to 2011R1.9 fails to properly validate or escape user-supplied input rendered by the Alert Heatmap report and the "My Reports" listing, resulting in stored cross-site scripting (CWE-79). An authenticated attacker with low privileges can inject script that executes in another user's browser context when they load the affected views.
Likely exposure
Organizations running Nagios XI versions earlier than 2011R1.9 with multiple authenticated users, especially where lower-privileged users can save report configurations that administrators later view, are exposed. Internet-exposed Nagios XI consoles increase risk further.
Exploitation context
Not listed in CISA KEV and no public reports of active exploitation are cited in the source bundle. Exploitation requires an authenticated attacker (PR:L) and victim interaction (UI:P) to load the poisoned report. CVSS 4.0 base is 5.1 with limited confidentiality and integrity impact on a secondary scope.
Researcher notes
CVSS 4.0 vector indicates network attack, low complexity, low privileges, and required user interaction with subsidiary confidentiality and integrity impact, consistent with stored XSS triggering in another user's session. Affected entry lists versions ["0"] with defaultStatus "unaffected", which is ambiguous; rely on the vendor changelog for the authoritative fixed build (2011R1.9). VulnCheck advisory is the primary third-party reference.
Mitigation direction
- Upgrade Nagios XI to version 2011R1.9 or later per vendor changelog.
- Restrict Nagios XI console access to trusted administrative networks or VPN.
- Review and prune untrusted or unused user accounts on the monitoring platform.
- Apply browser and CSP hardening on monitoring endpoints where feasible.
- Monitor Nagios XI audit logs for suspicious report creation or edits.
Validation and detection
- Confirm Nagios XI build version against the 2011R1.9 fix baseline.
- Inventory user accounts and roles able to create or edit reports.
- Test Alert Heatmap and My Reports views for script execution after patching.
- Review web server and application logs for unusual report parameter content.
- Verify session cookies on Nagios XI are HttpOnly and Secure.
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-2011-10039 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Medium
- CVSS
- 5.1 (4.0)
- Known Exploited
- No
- Published
Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA: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:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N——Primary CVE scoreVulnerability scoring details
Base CVSS 4.0 score
5.1MediumVector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N
Source materials
- CVE List V5 sourceCVE List V5
- https://www.nagios.com/changelog/nagios-xi/CVE reference · release-notes, patch
- https://www.vulncheck.com/advisories/nagios-xi-xss-via-alert-heatmap-report-and-my-reports-listingCVE 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.
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.