Malicious PDF — malware analysis report

Static analysis result for SHA-256 31c1dedd70eaecfa…

MALICIOUS

PDF

29.3 KB Created: 2021-07-21 10:42:55 +07:00 Authoring application: wkhtmltopdf 0.12.6 (via Qt 4.8.7) First seen: 2026-06-04
MD5: fd1c740db9837471bac01a3c91c712a3 SHA-1: 58077f43ad853728ea88914f6aeab291ffef72d4 SHA-256: 31c1dedd70eaecfa442e024266f73d70444a7decae45fe5e37637f907819618c
130 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file contains critical heuristic firings indicating it links to malicious redirector infrastructure, specifically promoting a "free generator / game hack". The embedded URL, http://netcdn.tw/app/431946152/how-to-buy-robux-for-free-game-hack, is the primary indicator of this lure. While no scripts were explicitly extracted, the nature of PDF exploits often involves embedded JavaScript for redirection or further payload execution, hence the inclusion of T1059.007. The overall goal appears to be tricking users into visiting a malicious site, likely for credential harvesting or malware delivery.

Machine Learning

  • Nyx PDF Classifier clean score 0.0556

Heuristics 4

  • PDF links to a 'free generator / game hack' redirector critical PDF_GAME_HACK_REDIRECT_LURE
    PDF's clickable action targets a redirector of the form /app/<id>/<slug>-game-hack — the landing-page shape of a large SEO 'free spins / generator / game hack' lure family that funnels victims through rotating disposable hosts to a malware/scam payload. The multi-link variants also trip ML/link-farm rules; this catches the single-link variants that otherwise score clean. CRITICAL on its own: the /app/<id>/<slug>-game-hack path shape is unambiguous scam infra, and the host rotates so a host-list match can't be relied on.
  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://netcdn.tw/app/431946152/how-to-buy-robux-for-free-game-hack In PDF document text
    • http://en.wikipedia.org/wiki/MIT_LicenseIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_002_off00001f7b.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x1F7B 22060 bytes
SHA-256: ac6b7a58528adf54821fc00c65851c2272bdcade0b995e86c249bece21dd7092
font_01_sfnt_off00005031.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x5031 18544 bytes
SHA-256: 91d288c248a30ed6e74be24ccff17ba7f2cc9913495eb801e969d2fad8023711

Open this report in the interactive analyzer, or submit your own file for analysis.