One day I was digging through my web server logs and came across a strange line: 185.63.253.2pp. At first glance it looks like an IP address—but it isn’t valid. That little “pp” at the end threw everything off. It made me pause and wonder: why would something like this appear in logs? Is it malicious? Or just a typo or internal tag?
What is 185.63.253.2pp?
At first glance, 185.63.253.2pp looks like it’s meant to be an IPv4 address with an extra suffix. But strictly speaking:
- A valid IPv4 address is four decimal numbers (each 0–255) separated by dots (e.g. 185.63.253.2)
- There can be no letters (“pp”) appended to the numeric form.
So as a network identifier, 185.63.253.2pp is invalid.
What likely happened is one of:
- Typo or data entry error — someone appended “pp” accidentally
- Internal tag or labeling — some system may append suffixes (e.g. “pp” meaning “proxy port,” “ping probe,” or other shorthand)
- Logging or concatenation artifact — two fields (IP + identifier) got merged without delimiter
- Obfuscation or trickery — used by a malicious actor trying to slip through pattern-based filters
In short: while 185.63.253.2pp is not a valid IP in networking, it’s a red flag in logs and deserves investigation.
Valid IPs vs. Invalid Formats: The Rules
To understand why 185.63.253.2pp breaks the rules, let’s review the correct format of IPv4 addresses:
- Four octets: each is a number from 0 to 255
- Dots separate the pieces
- No letters or extra symbols allowed in the numeric parts
Because of that, ”pp” or any other letters immediately make the string invalid.
Additionally, any systems or tools trying to parse or validate logs will likely reject or misinterpret it.
What’s the Real Underlying IP?
Because the numeric portion is 185.63.253.2, it’s natural to assume that is the “real” IP that was intended. Let’s see what we can learn about 185.63.253.2:
- It belongs to HostPalace Datacenters Ltd / HostPalace Cloud (ASN AS60064)
- Geolocation tools place it in Netherlands, specifically Amsterdam / North Holland region.
- It’s not currently flagged in abuse or threat databases (low-risk status) as of latest lookups.
So the real IP on its own is not especially suspicious—unless it starts showing nasty behavior (lots of failed logins, spam, etc.). The weird thing is the “pp” suffix.
Why Might “pp” Be Appended?
Here are some possibilities and what they imply:
1. Internal Label / Tagging
Some systems append short codes or tags to IPs to indicate context. For example, “pp” might mean proxy port, preprocessing pass, ping probe, policy path—whatever the system’s designer decided. If logs merge that tag with the IP in one field, you get something like 185.63.253.2pp.
2. Logging or Parsing Bug
If two fields are concatenated accidentally (IP field + suffix field) without a delimiter, you’ll see a malformed value. Maybe the system stored “185.63.253.2” in one column and “pp” in another, and some script joined them wrongly.
3. Obfuscation / Evasion
Attackers may deliberately alter IP-looking strings to bypass filters, pattern matching, or IP reputation checks. If a filter only identifies “185.63.253.*” but doesn’t expect letter suffixes, it might miss the entry entirely.
4. Test / Placeholder Value
In development, placeholders or dummy values are common. Someone might have used 185.63.253.2pp as a dummy, and it accidentally ended up in production logs.
5. Malformed Input from External Agent
Sometimes external traffic injects strange values in request headers or URL parameters, which then get logged by the system verbatim. If a malicious bot, script, or crawler used 185.63.253.2pp, your logs might simply record it.
Why It Matters When You See “185.63.253.2pp” in Logs
Seeing strings like this in logs is more than cosmetic — it can hide deeper issues or warnings. Here’s why you should pay attention:
- Confusion in Log Analysis
Tools that parse logs may skip or misread malformed entries. That means suspicious behavior may go unnoticed just because the IP is weirdly formatted. - Possible Security Threats
The anomaly might indicate automated scripts or bots using obfuscation to avoid detection. - Data Integrity Problems
Malformed entries often point to bugs in logging, data collection, or parsing systems. If one is wrong, others might be too. - False Alerts or Noise
If your SIEM, firewall, or alerting systems see 185.63.253.2pp, they may mis-classify or filter it, creating noise or gaps in coverage. - Tracing Difficulty
If something bad happened and you need to trace it, malformed entries make it harder to correlate logs, perform lookups, or investigate the source.
In short, malformed entries like 185.63.253.2pp degrade your observability and introduce uncertainty.
What to Do If You Encounter 185.63.253.2pp
Let me walk you through steps I used when I encountered a similar weird log entry (not exactly pp, but comparable). You can adapt this.
Step 1: Confirm and Isolate
- Search across all logs (web server, firewall, application logs) for 185.63.253.2pp and variants.
- Note timestamps, frequency, and adjacent log lines (what the user was requesting, any error codes).
- Check whether it always appears with the same suffix or different ones (e.g. “.2pp”, “.2qq”, etc.).
Step 2: Try to Map It to the Real IP
- Remove the suffix (“pp”) and test 185.63.253.2 in your tools (WHOIS, IP lookup).
- See if access patterns match (same time windows, endpoints).
- If possible, correlate with other log entries from 185.63.253.2 (without “pp”) to see if behavior aligns.
Step 3: Audit the Logging and Parsing Code
- Check whether your log formatting scripts or parsers might be combining fields incorrectly.
- Inspect any code that handles IP + tags, metadata, or label suffixing.
- Look especially at logging middleware, reverse proxies, or web servers that might add annotations.
Step 4: Monitor for Suspicious Behavior
- If 185.63.253.2pp appears in login attempts, form submissions, or unusual patterns (floods, brute-force behavior), flag it.
- Put the real IP 185.63.253.2 under watch (rate-limit, block temporarily if needed).
- Use firewall rules or WAF (web application firewall) filters to accept only properly formatted IPs, or block malformed ones.
Step 5: Clean Up or Filter
- If confirmed benign (typo or internal tag), you may safely filter out or normalize those entries in logs (strip the suffix) to standardize your dataset.
- If malicious or suspicious, you might blacklist the underlying IP (with caution) or alert your security team.
Step 6: Document and Prevent
- Document the cause and fix (bug, parsing issue, oversight).
- Add validation on data ingestion to reject malformed IP strings before logging.
- Add pattern-checking rules in your analytics or SIEM to flag any log entries containing letters in IP-like strings (i.e., anything like \d+\.\d+\.\d+\.\d+[a-zA-Z]+).
A Real-World Anecdote (From My Experience)
Let me share a short story from my own work:
While auditing logs for a web application, I once stumbled on entries like:
203.0.113.45xx – POST /login
203.0.113.45zz – POST /login
Initially, I thought it was a typo. But the occurrences were regular, coinciding with failed login attempts.
- I removed the “xx” / “zz” suffix and found those entries aligned with real IP 203.0.113.45.
- I realized the suffixes were being appended by a legacy middleware that tagged traffic as “xx” = extra login path, “zz” = backup path.
- That middleware was ill-designed: it merged metadata into the same field as the IP.
- The fix: change the middleware to store tags in a separate log field, and sanitize the IP field strictly.
By doing so, we eliminated a lot of confusion, improved alerting (we no longer missed failed login bursts), and cleaned our analytics pipeline.
I share this because these weird suffix patterns are often not malicious—just bad design. But ignoring them can degrade your visibility.
Conclusion
The string 185.63.253.2pp isn’t a proper IP address, but it’s meaningful. It’s a symptom—a flag in your logs that something unusual is happening. Whether it’s a simple bug, data formatting issue, an internal tagging system, or a deliberate obfuscation by an attacker, it should not be ignored.
Here are the key takeaways:
- 185.63.253.2pp is invalid as a networking address.
- The underlying IP 185.63.253.2 is legitimate and tied to HostPalace in the Netherlands.
- Suffixes like “pp” are likely tags, logging artifacts, or obfuscation.
- Investigate carefully—look for patterns, context, adjacent log lines.
- Fix log merging, add validation, and sanitize data to keep logs clean.
- Don’t block automatically—but monitor, rate-limit, or alert if behavior looks suspicious.
If you like, I can also prepare a more concise “for tech admins” checklist, or help you write a query or script to filter these malformed entries in your system. Which direction would you prefer next?
(FAQ)
Q: Could “pp” refer to a port number?
A: No, port numbers are indicated after a colon (e.g. :8080), not appended as letters. “pp” as letters doesn’t align with port syntax.
Q: Should I block 185.63.253.2 because of “pp”?
A: Not immediately. First, investigate whether the suffix is benign. If the underlying IP shows malicious behavior, you may consider blocking it—just don’t do it purely based on “pp”.
Q: Are there other weird suffix patterns people use?
A: Yes—some logs show things like 123.45.67.89_ab, 10.0.0.5TAG, or 192.168.1.1X. These are often internal tags or errors.
Q: Can an attacker use suffixes to bypass firewalls?
A: Possibly. If firewall or WAF rules match only strict IP regex, they may ignore or misinterpret suffix-laden entries. That’s why input validation and pattern-based detection are important.
Q: How common is this issue?
A: Not extremely common, but not rare either—especially in environments with custom logging, legacy systems, or complex tagging mechanics. Whenever you see a log entry that doesn’t conform, it’s worth investigating.
