Security readout for executives and security teams
Plain-English summary
Older versions of Nagios XI, a popular IT monitoring tool, do not properly clean up a value used in a link handler. An attacker who tricks a logged-in user into clicking a crafted link could run unwanted code in that user's browser session, potentially stealing dashboard data or hijacking actions inside Nagios XI.
Executive priority
Plan a routine upgrade to Nagios XI 2011R1.9 or later within the next standard maintenance window. Treat as moderate, not emergency, unless the Nagios XI console is internet-exposed or used by privileged operators.
Technical view
Nagios XI prior to 2011R1.9 fails to sufficiently validate or escape user-supplied input in the backend_url JavaScript link handler, enabling cross-site scripting (CWE-79). An authenticated attacker can craft input that, when rendered to another user, executes arbitrary script in that user's browser context with the Nagios XI session.
Likely exposure
Organizations running Nagios XI versions prior to 2011R1.9 with the affected backend_url handling. Risk concentrates where the Nagios XI web console is reachable by users beyond a small admin group, especially internet-exposed monitoring portals.
Exploitation context
No public exploitation is cited in the bundle and the CVE is not on CISA KEV. Exploitation requires an authenticated attacker to deliver a crafted link or page and a victim user to interact with it, which limits scale but is plausible against monitoring teams.
Researcher notes
CWE-79 reflected/stored XSS in the backend_url JavaScript link handler. CVSS 4.0 5.1 with PR:L and UI:P indicates authenticated attacker plus victim interaction, with low confidentiality and integrity impact on a subsequent component. No PoC, KEV entry, or in-the-wild reports are cited in the bundle. Validate by enumerating Nagios XI build versions and reviewing backend_url usage in custom dashboards or links.
Mitigation direction
- Upgrade Nagios XI to version 2011R1.9 or later per the vendor changelog.
- Restrict access to the Nagios XI web console to trusted networks and authenticated operators.
- Apply browser and WAF protections that block reflected script payloads to the monitoring portal.
- Review Nagios XI user privileges and reduce accounts that can craft or share backend_url links.
- Confirm fix coverage with the vendor advisory before closing the ticket.
Validation and detection
- Inventory Nagios XI instances and record their exact build numbers against 2011R1.9.
- Cross-check identified versions with the Nagios XI changelog fix notes.
- Review the VulnCheck advisory for any indicators of the vulnerable backend_url path.
- Audit web logs for unusual backend_url parameters delivered to authenticated users.
- Confirm post-upgrade that the backend_url handler safely encodes injected payloads in a controlled test.
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-2011-10036 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-backend-url-javascript-link-handlerCVE 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.