Check-Host.cc

IP Address IPv4

147.91.80.21

Aggregated from public BGP, CT logs, our scan layer, honeypots and global probes.

Run a live full scan of 147.91.80.21

On-demand: ports, banners, TLS, tech-stack, subdomains and origin/IP-leak detection. Results are shared publicly for everyone to link to.

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ASN
AS13092
Click for details
Country
RS
Serbia
Reverse DNS
redcap.ipb.ac.rs
PTR
Open Ports
2
Last scan

Autonomous System

ASN
AS Name
AS Type
RIR
RIPE NCC
Allocated
2000-03-16
Allocation status
Assigned

Geolocation

Country
RS · Serbia
Continent
Europe
Source
MaxMind GeoLite2

Reverse DNS

Last seen
2026-07-19 05:35:49

Network

Prefix
RPKI

Open Ports

Port Proto Service Server Last seen
80 tcp http Apache/2.4.65 (Debian) 2026-07-19 05:35:05.000
443 tcp https Apache/2.4.65 (Debian) 2026-07-17 23:25:46.000

TLS Certificates

Port 443 d947777135f8…
Subject: redcap.ipb.ac.rs
Issuer: YE2
SANs: redcap.ipb.ac.rs
Valid 2026-06-22 18:28:41 → 2026-09-20 18:28:40

Tech Stack

Detected via Wappalyzer-style rules on the HTTP response body, headers, scripts and meta tags.

Origin / IP-Leak

USP

When a hostname is served behind a CDN (e.g. Cloudflare), the origin server can sometimes be identified by matching its TLS cert against the protected hostname. Findings shown here are heuristic candidates, not guarantees.

No origin-leak candidates for this IP

When this IP serves a TLS cert for a domain that fronts behind a CDN, that domain surfaces here as an origin-leak candidate with a confidence score.

Hosted Domains

1 domain resolve (A-record) to this IP.

Multi-Vantage Check

Reachability accrued passively from real user-triggered checks across our 65+ probe nodes. Run a live check to add fresh data.

ICMP responsive This IP replied to our global ICMP sweep — last confirmed 2026-08-05.

No accumulated reachability data yet

Reachability accrues from real user-triggered checks. Trigger a Ping or HTTP check from our 65+ probe nodes to contribute the first data point.

Web Pages

Login panel served on port 443 — a sign-in form is exposed to the internet.

Port Page title Status Flags
443 REDCap 200 login
80 Apache2 Debian Default Page: It works 200

Threat Intelligence

No threat-intel matches

This IP doesn't appear in any of the feeds we mirror (Tor exits, FireHOL Level 1-3, Spamhaus DROP/EDROP, URLhaus, OpenPhish). Absence here doesn't prove the IP is clean — it just means none of our public-feed sources flag it.

Co-Hosted Domains

Domains this host references in its HTML AND whose DNS A/AAAA record resolves back to this IP — i.e. actually hosted here.

redcap.ipb.ac.rs DNS-confirmed

External References

Domains the body links to whose DNS does NOT resolve to this IP — usually CDN assets, embeds, or third-party services. Boilerplate (Google Fonts, jsDelivr, w3.org…) is already filtered.

projectredcap.org href · ×1
redcap.vumc.org href · ×1
httpd.apache.org href · ×1
bugs.debian.org href · ×1

History

First observed
2026-07-17 23:25
Last observed
2026-07-19 05:35
Scan observations
4

The full change-log (ASN moves, cert rotations, port-state diffs) accumulates as our archives grow.