Malicious PDF — malware analysis report

Static analysis result for SHA-256 139397614ff4467d…

MALICIOUS

PDF

30.0 KB Created: 2021-07-22 18:00:34 +07:00 Authoring application: wkhtmltopdf 0.12.6 (via Qt 4.8.7) First seen: 2026-06-04
MD5: 07daec59f40b4a8d689aa00e1ac96b39 SHA-1: bf8efb15b13731be2cda198f243579c6f7e27435 SHA-256: 139397614ff4467d7313e37e7310bddc0a3eb2bab4a53e99839c213bdb74023c
130 Risk Score

Malware Insights

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

The PDF file contains multiple links to a known malicious redirector, masquerading as a 'free generator' or 'game hack'. The document body and embedded metadata reinforce this lure. The primary malicious URL identified is http://netcdn.tw/app/431946152/free-robux-no-verification-needed-game-hack, which is likely used to deliver a second-stage payload.

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/free-robux-no-verification-needed-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
font_00_sfnt_off00001df1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1DF1 22976 bytes
SHA-256: 08f652b2bba699ae652c2cb64f70ec4604d1815ba7715f0d3a8ae000f15b1a1d
font_01_sfnt_off000051c1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x51C1 18960 bytes
SHA-256: f84c00a5f4de0f0f56267fefbe81f6503166d680d0fb608a7d78e26982bbbcac