Malicious PDF — malware analysis report

Static analysis result for SHA-256 84e20f97c969f7b7…

MALICIOUS

PDF

47.0 KB Created: 2021-06-04 03:37:24 +07:00 Authoring application: wkhtmltopdf 0.12.6 (via Qt 4.8.7) First seen: 2021-10-24
MD5: 8b195783dee00b8cfdf3d788e92bfded SHA-1: 364fde3b5368f5dbfd068af0e57f9a280721f9d9 SHA-256: 84e20f97c969f7b70b085bc2a3145062239003ae7eb202742a2e3b84579aba85
320 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains multiple heuristics indicating malicious intent, including links to known malicious redirectors and a fake CAPTCHA lure. The document body and embedded URLs promote free game currency and hacks, aiming to trick users into clicking malicious links. The presence of numerous PDF links suggests an attempt to create a link farm for SEO manipulation or to distribute further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9769

Heuristics 7

  • 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.
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • Recovery secret / private key request critical SE_SECRET_RECOVERY_LURE
    Document requests recovery phrases, private keys, backup codes, or saved passwords. Requests for these secrets in a document are high-risk.
  • 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.online/app/406889139/coin-master-daily-free-spins-link-download-game-hack In PDF document text
    • http://e-library.akademitelkom.ac.id/repository/coin-master-free-coins-app_GM406889139.pdfIn PDF document text
    • http://e-library.akademitelkom.ac.id/repository/coin-master-rewards-free-spins_GM406889139.pdfIn PDF document text
    • http://e-library.akademitelkom.ac.id/repository/coin-master-daily-free-spins-link-today_GM406889139.pdfIn PDF document text
    • http://e-library.akademitelkom.ac.id/repository/coin-master-free-spins-link-2021-today_GM406889139.pdfIn PDF document text
    • http://e-library.akademitelkom.ac.id/repository/coin-master-free-spin-and-coins-links_GM406889139.pdfIn PDF document text
    • http://e-library.akademitelkom.ac.id/repository/free-spins-on-coin-master-link_GM406889139.pdfIn PDF document text
    • http://e-library.akademitelkom.ac.id/repository/how-to-get-free-robux-without-verification_GM431946152.pdfIn PDF document text
    • http://e-library.akademitelkom.ac.id/repository/free-spin-links-coin-master-october-30-2021_GM406889139.pdfIn PDF document text
    • http://e-library.akademitelkom.ac.id/repository/blogspot-coin-master-free-spins_GM406889139.pdfIn PDF document text
    • http://e-library.akademitelkom.ac.id/repository/minecraft-free-download-android_GM479516143.pdfIn PDF document text
    • http://e-library.akademitelkom.ac.id/repository/free-robux-pastebin_GM431946152.pdfIn PDF document text
    • http://e-library.akademitelkom.ac.id/repository/roblox-catalog-free_GM431946152.pdfIn PDF document text
    • http://e-library.akademitelkom.ac.id/repository/roblox-how-to-hack-peoples-accounts-2021_GM431946152.pdfIn PDF document text
    • http://e-library.akademitelkom.ac.id/repository/coin-master-hacks-free-spins_GM406889139.pdfIn PDF document text
    • http://e-library.akademitelkom.ac.id/repository/claim-free-robux_GM431946152.pdfIn PDF document text
    • http://e-library.akademitelkom.ac.id/repository/free-robux-not-fake_GM431946152.pdfIn PDF document text
    • http://e-library.akademitelkom.ac.id/repository/free-coins-coin-master-blog_GM406889139.pdfIn PDF document text
    • http://e-library.akademitelkom.ac.id/repository/free-robux-no-verification-2021_GM431946152.pdfIn PDF document text
    • http://e-library.akademitelkom.ac.id/repository/are-robux-generators-safe_GM431946152.pdfIn PDF document text
    • http://e-library.akademitelkom.ac.id/repository/free-spin-coin-master-online_GM406889139.pdfIn PDF document text
    • http://en.wikipedia.org/wiki/MIT_LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_004_off0000514a.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x514A 24336 bytes
SHA-256: 3d37911bf369a314be40d508f618b9b085a3e73dfc0bed7a741380239d197e75
font_01_sfnt_off00008985.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x8985 2820 bytes
SHA-256: e5f6ec650849eefe6bc6a1649c2875ce35328d23e4196945bba66cc43e5a49d4
font_02_sfnt_off00009324.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x9324 18816 bytes
SHA-256: 9c26c181c4cdabeaa0059472f140f722c9ebd74ce71ebd91f88ed40d9942d1a6