Opens an authenticated DWR path without credentials. Advisory
Detect
Fingerprints N-central and flags CVE-2026-18577 by version.
Report
Counts checked, product, affected, and confirmed.
Targets
Hosts, IPs, or URLs, one per line. Empty input uses localhost.
Overview
This workflow finds N-able N-central and sorts each host by whether its version falls in the CVE-2026-18577 range. N-central is the RMM that already has admin over a customer fleet. CVE-2026-18577 is authentication bypass that CISA listed on KEV. A forgotten 2026.3.x console on a partner VLAN still answers the same login you already know. Give it hostnames, IP addresses, or URLs you are authorised to test. The workflow fingerprints the product from the public page (title match on N-central), reads the version from /login with a fallback to the root body, and compares that number to the range table in the graph. Every host comes back affected or not, so a fleet advisory becomes an evidenced list for exposure management. CVE-2026-18577 is on CISA KEV (known exploited). Version flag is first. Hosts in range get a second node that only opens an authenticated DWR path without credentials. It does not log in or write files.
Run it on a schedule when the estate changes. New hosts and delayed patch windows are the reason the same check is worth more the second week than the first.
Pipeline
Read the target list. Hosts, URLs, or ranges, one per line, become the scope.
Fingerprint each host as N-able N-central from the public page title, then GET /login and parse the version. A host counts as affected only when the fingerprint matches and the version is inside the encoded range.
Confirm only those flagged hosts by opening an authenticated DWR path without credentials.
Collect the per-host rows: product match, version, affected flag, confirmed flag, and any fetch error.
Emit the summary counts: hosts checked, product hits, affected, confirmed, and errors.
Inputs
Target list. Hostnames, IP addresses, CIDR ranges, or URLs, one per line. JSONL with a url field also works. Point it at scope you are authorised to test. Fingerprint is read-only GET. Confirm is a GET of an authenticated DWR path, and only after the version flag.
Outputs
results.jsonl. One row per host: URL, whether N-able N-central was detected, the version read, the affected flag, and whether the DWR confirm succeeded.
summary.json. Counts across the list: targets, product hits, affected, and errors.
Integrations
HTTP. Unauthenticated GET to the product root, /login, and (on flagged hosts only) an authenticated DWR path.
Sample output
The records below are illustrative and do not come from a real run. They show one N-able N-central host inside the CVE-2026-18577 range, one patched host, and one host that is not the product.
Every build through 2026.3.1 inclusive. Builds after 2026.3.1 is the floor the graph treats as not affected. The compare uses the version the product itself served.
Does a flagged host mean CVE-2026-18577 was exploited?
No. A flagged row is patch-lag against the range table. Confirm only opens an authenticated DWR path without credentials. Treat a confirmed row as evidence the bypass still answers, not as proof someone already used it.
Is this check safe on production?
Yes. Fingerprint is read-only GET. Confirm is a GET of an authenticated DWR path without credentials, only on hosts already in range. It does not log in or write files.
Does the check need credentials?
No. It fingerprints the public page and reads /login the way an external scanner would.
What is CVE-2026-18577?
Authentication bypass in N-able N-central. CISA listed it on KEV. The ceiling in the graph is 2026.3.1 inclusive. This workflow flags by version, then confirms by opening an authenticated DWR path without credentials.