Malicious PDF — malware analysis report

Static analysis result for SHA-256 51f31f13c478516e…

MALICIOUS

PDF

49.2 KB Created: 2021-06-10 18:42:51 +07:00 Authoring application: wkhtmltopdf 0.12.6 (via Qt 4.8.7) First seen: 2026-06-04
MD5: 127aa28bf52458bef6da9e6c9be3a116 SHA-1: 6abf3994cfee6dd133c27aa75336efd3b8b2b1f1 SHA-256: 51f31f13c478516e26949bcff48833e30696460a56c7b91cd6a4b49d5e0c8212
160 Risk Score

Malware Insights

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

The PDF contains a critical heuristic firing for a game hack redirect lure, pointing to a URL that is also flagged as a malicious redirector. The document body, though partially garbled, contains text related to 'free Robux' and 'game hack', reinforcing the lure. The embedded link likely leads to a phishing or malware download site.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9796

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 https://netcdn.tw/app/431946152/hack-for-free-fake-ptomocodes-that-give-robux-game-hack In PDF document text
    • https://pasca.unisba.ac.id/elibrary/repository/is-it-possible-to-get-free-robux_GM431946152.pdfIn PDF document text
    • https://pasca.unisba.ac.id/elibrary/repository/toolbox-apk_GM479516143.pdfIn PDF document text
    • https://pasca.unisba.ac.id/elibrary/repository/coin-master-hack-with-facebook-login_GM406889139.pdfIn PDF document text
    • https://pasca.unisba.ac.id/elibrary/repository/free-spins-link-in-coin-master-2021_GM406889139.pdfIn PDF document text
    • https://pasca.unisba.ac.id/elibrary/repository/coin-master-free-spins-iphone-2021_GM406889139.pdfIn PDF document text
    • https://pasca.unisba.ac.id/elibrary/repository/roblox-fly-hack_GM431946152.pdfIn PDF document text
    • https://pasca.unisba.ac.id/elibrary/repository/robux-scam_GM431946152.pdfIn PDF document text
    • https://pasca.unisba.ac.id/elibrary/repository/how-to-change-roblox-username-for-free-2021_GM431946152.pdfIn PDF document text
    • https://pasca.unisba.ac.id/elibrary/repository/op-rewards-robux_GM431946152.pdfIn PDF document text
    • https://pasca.unisba.ac.id/elibrary/repository/roblox-any-gamepass-for-free_GM431946152.pdfIn PDF document text
    • https://pasca.unisba.ac.id/elibrary/repository/how-to-get-free-robux-easy-1-munuit_GM431946152.pdfIn PDF document text
    • https://pasca.unisba.ac.id/elibrary/repository/roblox-hacks-for-mac_GM431946152.pdfIn PDF document text
    • https://pasca.unisba.ac.id/elibrary/repository/rblx-city-free-robux_GM431946152.pdfIn PDF document text
    • https://pasca.unisba.ac.id/elibrary/repository/free-coin-master-spins-link_GM406889139.pdfIn PDF document text
    • https://pasca.unisba.ac.id/elibrary/repository/coin-master-free-spins-and-coins-app_GM406889139.pdfIn PDF document text
    • https://pasca.unisba.ac.id/elibrary/repository/minecraft-hacks-xbox-one_GM479516143.pdfIn PDF document text
    • https://pasca.unisba.ac.id/elibrary/repository/free-spin-in-coin-master_GM406889139.pdfIn PDF document text
    • https://pasca.unisba.ac.id/elibrary/repository/spin-coin-master_GM406889139.pdfIn PDF document text
    • https://pasca.unisba.ac.id/elibrary/repository/promo-codes-to-get-free-robux_GM431946152.pdfIn PDF document text
    • https://pasca.unisba.ac.id/elibrary/repository/instant-robux_GM431946152.pdfIn PDF document text
    • http://en.wikipedia.org/wiki/MIT_LicenseIn PDF document text

Related samples 8

Ranked by shared artifacts, heuristics, extracted URLs, CVEs, and signatures.

Full JSON: related samples API

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_004_off0000556d.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x556D 25240 bytes
SHA-256: 69f23e3c97fd2bafcb556d4cd41d217aef870e6c28c574565810c71f7642a2f3
font_01_sfnt_off00008f9e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x8F9E 3096 bytes
SHA-256: d05729863dc05721ada29044278030255eeda038236568e8246a87d3a8573d6e
font_02_sfnt_off00009a49.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x9A49 19504 bytes
SHA-256: dcc520bb50115ca56d0ec4cf66954c6c3ab3e73ec18fc1a92d0859470519ed85

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