Malicious PDF — malware analysis report

Static analysis result for SHA-256 77737cbcc9cdd13b…

MALICIOUS

PDF

88.5 KB Created: 2021-07-21 21:46:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 3c05d79a8703eb366b0fe9f16f5a40d6 SHA-1: a15c49ccce3e34b2691e7c834b3b8c4931f1342f SHA-256: 77737cbcc9cdd13b751fb322d9230d2ac23dd278d00f1fcfc1f11c6f8373772d
96 Risk Score

Malware Insights

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

The PDF file contains a link farm pointing to numerous compromised websites, many of which are hosted on disposable domains or use WordPress upload vulnerabilities. The ML classifier strongly indicates maliciousness. The primary function appears to be redirecting users to potentially malicious content, likely serving as a lure for phishing or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

Heuristics 5

  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • 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://ndc-group.ru/uploads/files/79103333112.pdf In PDF document text
    • https://aglogistics-bo.net/userfiles/file/duzabigigunive.pdfIn PDF document text
    • https://eatorhours.org/e-bussiness/fckimages/file/xogirizolezelerofevapo.pdfIn PDF document text
    • http://gaushalango.com/uploaded_files/userfiles/files/pulaxenagimufab.pdfIn PDF document text
    • http://planbmedia.hufiles/26605570875.pdfIn PDF document text
    • https://canadianrelocation.net/wp-content/plugins/formcraft/file-upload/server/content/files/16092c79dbb8ba---64103126828.pdfIn PDF document text
    • https://edinburghpools.com/contents//files/vawusawagenopobakefe.pdfIn PDF document text
    • https://trungtammatnamviet.vn/upload/files/99478801731.pdfIn PDF document text
    • https://bladmedyczny24.pl/wp-content/plugins/super-forms/uploads/php/files/97e1a57b2cbcdae6f15a2de33e5d454d/ruresobitazojudifanonawex.pdfIn PDF document text
    • http://yilip.net/userData/board/file/gamepetifuf.pdfIn PDF document text
    • https://vnnc.vn/img-hdmedia/files/xodesagixogubaporanegizov.pdfIn PDF document text
    • http://stark-tools.ru/images/uploaded/32851765795.pdfIn PDF document text
    • http://chemicalengineers.ie/images/16362709505.pdfIn PDF document text
    • http://tamlaproject.com/userData/board/file/38402611857.pdfIn PDF document text
    • https://wscnaturalhealings.com/wp-content/plugins/super-forms/uploads/php/files/e3840ac17d8b77971f98776063d320d3/9492158210.pdfIn PDF document text
    • http://andlupa.com/userfiles/file/92643751946.pdfIn PDF document text
    • http://smartcookieacademy.com/wp-content/plugins/formcraft/file-upload/server/content/files/16091690214696---22017354335.pdfIn PDF document text
    • http://irmascaritasdejesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608aa4b0cfdb1---38424881985.pdfIn PDF document text
    • https://goldenparadisestsimons.com/wp-content/plugins/super-forms/uploads/php/files/9adb84083a662a654917737b47f3128b/85506853493.pdfIn PDF document text
    • https://sirikulsteel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d7e5f238df---25531990903.pdfIn PDF document text
    • https://www.bocamvigliesrooms.com/wp-content/plugins/super-forms/uploads/php/files/05d4064490b082395161263e2bdd7f66/polemiga.pdfIn PDF document text
    • https://fl-forever.com/upfiles/editor/files/45271306512.pdfIn PDF document text
    • http://www.empresasdelimpeza.info/wp-content/plugins/formcraft/file-upload/server/content/files/1607a89e41bad3---76405908943.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=paragraph+of+my+daily+lifePDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f985.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF985 10692 bytes
SHA-256: 4b37e7c11ace9cf7ae9d435354e6a696a1c396e9383e7e145387c43409829e14
font_01_sfnt_off000111c3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x111C3 16652 bytes
SHA-256: f333bdd56696db6ba7e23ea1705da3148e2d0de9132395b04bd768a175e62c53
font_02_sfnt_off00013c9c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13C9C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1