Skip to content
View Metercedes's full-sized avatar

Highlights

  • Pro

Block or report Metercedes

Block user

Prevent this user from interacting with your repositories and sending you notifications. Learn more about blocking users.

You must be logged in to block users.

Content in all repositories owned by your account will be closed.
Maximum 250 characters. Please don’t include any personal information such as legal names or email addresses. Markdown is supported. This note will only be visible to you.
Report abuse

Contact GitHub support about this user’s behavior. Learn more about reporting abuse.

Report abuse
Metercedes/README.md

Kamil Mete Yalçınkaya

Cybersecurity student in Warsaw. I build detection and analysis tooling, and I break my own applications before someone else does.

Most of what I write ends up being about the gap between a control existing and a control working. A rule that has never been tested against telemetry is a guess. A checksum with a constant salt is tamper-evidence, not authentication. An encryption key that regenerates on restart silently makes its own data unreadable. Those distinctions are what the repositories below are actually about.

Detection and response

detection-engineering-lab — 15 Sigma detections for Windows, Linux and authentication telemetry, with an offline evaluator so every rule can be validated against deterministic telemetry without a SIEM. Each rule ships the events it must match and a benign baseline it must not. 18 ATT&CK techniques, 139 tests.

sentinel-kql-detections — 10 Microsoft Sentinel analytics rules and 3 hunting queries across Entra ID, Defender and the Windows Security log, plus a static analyser that resolves every column reference against checked-in table schemas. A mistyped column makes a Sentinel rule return nothing forever without any error. 14 ATT&CK techniques, 68 tests.

soc-triage-toolkit — Turns a reported phishing message into an analyst report: which headers disagree, where it really came from, what the attachments hash to, every indicator extracted and defanged. Evidence rather than a score.

network-incident-triage — PCAP triage in pure Python: flows, DNS, TLS server names, HTTP metadata, and detection of scans and beaconing. The parser is written from the format specifications and checked against tshark on every fixture.

Application and supply-chain security

secure-notes-api — Spring Boot REST API with rotating refresh tokens, replay detection that revokes the whole token family, and per-owner access control proved by negative tests. The build fails on a dependency with a known critical vulnerability, which it currently catches.

secure-recruitment-platform — A university project of mine, reviewed as if it were someone else's code. Twelve findings, worst of them an authentication bypass through a client-supplied header, each fixed with a regression test. The vulnerable code stays in the history so the review can be checked against it.

vulnerability-prioritization-workbench — Reconciles Trivy and Grype output into one set of findings, enriches with CISA KEV and EPSS, and orders remediation with a stated reason for every decision. On the sample scan, 262 raw findings are the same 131 vulnerabilities.

Reverse engineering

save-format-research — Working out what an unknown binary container is: entropy and signature triage, telling obfuscation apart from encryption, recovering a repeating-key XOR from ciphertext alone, and identifying which digest construction produced a checksum from one known-good file.

Working with

Python, Java, Bash, KQL. Sigma, MITRE ATT&CK, Elastic Security, Microsoft Sentinel, Defender XDR, Wireshark and tshark. Spring Security, OWASP Top 10, CVSS, EPSS, CISA KEV, Trivy, Grype, CodeQL, SBOM and CI security gates.

Education

Cybersecurity, Uniwersytet VIZJA, Warsaw. VKV Koç School. IELTS Academic 6.5.

Contact

ymete089@gmail.com

Popular repositories Loading

  1. Steam--Clorthax-s-Summer-Sale-Quest-Script Steam--Clorthax-s-Summer-Sale-Quest-Script Public archive

    Browser script for a 2022 Steam summer sale event. Archived; the event has ended.

    7

  2. AEH_BP24L AEH_BP24L Public archive

    First-year university programming coursework in Java, one branch per lab. Archived.

    Java 1

  3. secure-recruitment-platform secure-recruitment-platform Public

    University job board reviewed as unfamiliar code: twelve findings including an authentication bypass via a client-supplied header, each fixed and held by a regression test.

    Java 1

  4. secure-notes-api secure-notes-api Public

    Spring Boot REST API with rotating refresh tokens, replay detection and per-owner access control, verified by negative authorisation tests and an SBOM-scanned build.

    Java 1

  5. detection-engineering-lab detection-engineering-lab Public

    Sigma detections for Windows, Linux and authentication telemetry, with an offline evaluator that proves each rule fires on its technique and stays silent on a benign baseline.

    Python 1

  6. sentinel-kql-detections sentinel-kql-detections Public

    Microsoft Sentinel analytics rules and hunting queries for Entra ID, Defender and Windows telemetry, with a KQL static analyser that resolves every column reference against table schemas.

    Python 1