Malicious PDF — malware analysis report

Static analysis result for SHA-256 bc57084e50b2e7b6…

MALICIOUS

PDF

54.6 KB Created: 2021-06-08 12:29:58 +07:00 Authoring application: wkhtmltopdf 0.12.6 (via Qt 4.8.7) First seen: 2021-09-16
MD5: b367c6f971d1b1c5f31bdd8066533572 SHA-1: 342190337da86392ba639c383b9d2c85898ccae0 SHA-256: bc57084e50b2e7b6d844ca6b9f64feb24db06c1fc2c6b14ed770da811d037fb0
160 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains multiple links to known malicious redirectors and lures users with promises of game hacks and free currency. The ML classifier also flagged this PDF as malicious. The embedded URLs likely lead to a second-stage download or phishing page.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9523

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/hightlighter-player-roblox-cheat-game-hack In PDF document text
    • http://zercalo.org/images/free-daily-spins-coin-master_GM406889139.pdfIn PDF document text
    • http://zercalo.org/images/free-robux-hack-no-human-verification-or-survey_GM431946152.pdfIn PDF document text
    • http://zercalo.org/images/how-to-get-minecoins-in-minecraft-for-free_GM479516143.pdfIn PDF document text
    • http://zercalo.org/images/how-to-get-minecraft-for-free-on-android_GM479516143.pdfIn PDF document text
    • http://zercalo.org/images/free-roblox-accounts-with-robux-2021_GM431946152.pdfIn PDF document text
    • http://zercalo.org/images/roblox-top_GM431946152.pdfIn PDF document text
    • http://zercalo.org/images/minecraft-hacked-client_GM479516143.pdfIn PDF document text
    • http://zercalo.org/images/free-minecraft-bedrock-server-hosting_GM479516143.pdfIn PDF document text
    • http://zercalo.org/images/how-do-i-get-free-spins-on-coin-master_GM406889139.pdfIn PDF document text
    • http://zercalo.org/images/free-robux-gen_GM431946152.pdfIn PDF document text
    • http://zercalo.org/images/free-spins-and-coins-for-coin-master_GM406889139.pdfIn PDF document text
    • http://zercalo.org/images/coin-master-hacks-2021_GM406889139.pdfIn PDF document text
    • http://zercalo.org/images/free-promo-codes-for-robux_GM431946152.pdfIn PDF document text
    • http://zercalo.org/images/free-robux-legit-2021_GM431946152.pdfIn PDF document text
    • http://zercalo.org/images/free-spin-in-coin-master_GM406889139.pdfIn PDF document text
    • http://zercalo.org/images/coin-master-daily-gift-free-spins-and-coins-link_GM406889139.pdfIn PDF document text
    • http://zercalo.org/images/minecraft-windows-10-edition-free_GM479516143.pdfIn PDF document text
    • http://zercalo.org/images/coin-master-apk-hack-35-8_GM406889139.pdfIn PDF document text
    • http://zercalo.org/images/how-to-hack-roblox_GM431946152.pdfIn PDF document text
    • http://zercalo.org/images/how-can-you-get-free-robux_GM431946152.pdfIn PDF document text
    • http://en.wikipedia.org/wiki/MIT_LicenseIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_004_off00005347.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x5347 27680 bytes
SHA-256: bf441217aedd4fee43903e87ec6d13f3ae61e1c46b50b06e707a4bdf058316e2
font_01_sfnt_off00009382.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x9382 5180 bytes
SHA-256: e26bd73f7c230d1d1b353c9559e30e7c585d1768f7cebbf523de88a345db2651
font_02_sfnt_off0000a46f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xA46F 3396 bytes
SHA-256: e59bc53cd4c0ee65dc1533becad2866f345dcb060e6c68bb8187d21cb9f973ee
font_03_sfnt_off0000b061.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB061 19024 bytes
SHA-256: 5263b2124163b6499b2c0ef1a7235ac5c06508af3222b9bd748bb4030785fa76