Malicious PDF — malware analysis report

Static analysis result for SHA-256 835ef8a63c10715a…

MALICIOUS

PDF

36.2 KB Created: 2021-05-11 09:07:30 +07:00 Authoring application: wkhtmltopdf 0.12.6 (via Qt 4.8.7) First seen: 2021-10-26
MD5: fe66f6905f7ddc74322dcad2902497ac SHA-1: d3b06ca1091c4dd8a5e4a69b601a0ea6834ff8a5 SHA-256: 835ef8a63c10715a22c00cb5359702dfbb059333d28465f234446168eef90d22
170 Risk Score

Malware Insights

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

The PDF document contains a malicious link disguised as a "free generator" or "game hack" to trick users into clicking it. It also displays a fake CAPTCHA, further pressuring the user to interact with the malicious content. The primary malicious URL identified is https://netcdn.xyz/app/431946152/give-me-free-robux-game-hack, which is associated with redirector infrastructure.

Machine Learning

  • Nyx PDF Classifier clean score 0.0302

Heuristics 5

  • 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.
  • Fake CAPTCHA / human verification prompt high SE_FAKE_CAPTCHA
    Document displays a fake CAPTCHA or human-verification prompt — used to trick users into running commands or pressing keyboard shortcuts
  • 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 https://netcdn.xyz/app/431946152/give-me-free-robux-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_003_off0000339b.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x339B 24340 bytes
SHA-256: dfcc13fd5598b7bbf6ffb41c86331bb830709d2e8ec06bec8d1587e4df22f0b3
font_01_sfnt_off00006b7d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x6B7D 18444 bytes
SHA-256: 68319dbf483afe81c5a4de3b3f5290fc223d358c0f75f000dd988daf46eb7eae