Malicious PDF — malware analysis report

Static analysis result for SHA-256 caf18ca17f2d2671…

MALICIOUS

PDF

127.5 KB Created: 2021-06-10 02:55:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 5ffdd8213f7f858cecc02c580257e286 SHA-1: ef848232e3ab3a352b1613d894cb2b8f15b5901f SHA-256: caf18ca17f2d26717722d68d44e7aaf12bc047d852f5e4ca9451f2b781c60705
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file contains a large number of external links, many pointing to disposable hosting services, indicating a link farm or SEO manipulation tactic. The ML classifier strongly flagged this PDF as malicious. While no scripts were explicitly extracted, the presence of numerous external links suggests an attempt to redirect users to potentially malicious content, possibly leveraging embedded JavaScript for obfuscation or further redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 5

  • 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.
  • 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 https://wastran.ru/pbw?utm_term=color+vision+test+book+pdf+download PDF link annotation
    • https://ralubimuxafoku.weebly.com/uploads/1/3/4/3/134373731/ea522.pdfIn PDF document text
    • https://gumotamilo.weebly.com/uploads/1/3/5/3/135319527/juxaxazesafilax_vofolag_pelavisuzezan.pdfIn PDF document text
    • https://static.s123-cdn-static-d.com/uploads/4482415/normal_60b485e5ef145.pdfIn PDF document text
    • https://jokazetesolibut.weebly.com/uploads/1/3/5/3/135314514/fixarevuli.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4421623/normal_60bf666f28728.pdfIn PDF document text
    • https://zebepinexorusog.weebly.com/uploads/1/3/2/6/132695607/172de3691d36.pdfIn PDF document text
    • https://kowasazupajobex.weebly.com/uploads/1/3/1/3/131383373/xusat-raluna-xufofabaredukip.pdfIn PDF document text
    • https://kenometiwu.weebly.com/uploads/1/3/4/3/134340836/mowibawuketane_gilevalumi_bekugotisot_bejikuzas.pdfIn PDF document text
    • https://mejepizejuv.weebly.com/uploads/1/3/4/5/134528376/05999dd5942aba.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4408702/normal_6041b685e39cb.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://jutifakukap.pbworks.com/w/file/fetch/144508335/92979971404.pdfIn PDF document text
    • http://mutoteja.pbworks.com/w/file/fetch/144510498/lefokonidutobuxewuwexo.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4cab7808-9cd0-46f7-8cd7-8724eadb3c67/64856515382.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b138d92a-fb37-439f-b798-d939535c3eb4/the_human_condition_movies.pdfIn PDF document text
    • http://sapagujedok.pbworks.com/w/file/fetch/144993843/dragon_ball_legends_hack_ios_2020.pdfIn PDF document text
    • http://viruniruxo.pbworks.com/f/28790247469.pdfIn PDF document text
    • http://joraxakegeg.pbworks.com/f/the_hills_have_eyes_2_dual_audio_720p_download.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/92883564-0529-4ca0-a1cb-7215cabe9839/sapetipimotolij.pdfIn PDF document text
    • http://xutosop.pbworks.com/f/best_pvp_comps_afk_arena.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c41e38fe-8d77-4110-8932-cccbea827ca8/hedgehog_bookmark_template.pdfIn PDF document text
    • 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://scripts.sil.org/OFLIn 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_off00019d81.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x19D81 5296 bytes
SHA-256: 6d49cadef28d0aee190013f3fe61bb7e83ca59f230ca36c9aff11504f718c36c
font_01_sfnt_off0001afa2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1AFA2 13428 bytes
SHA-256: 3ef31bfce9d3a982332bdaeef630d09f481f54d6c8b705b57df1ccbcc9362c1b
font_02_sfnt_off0001daff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1DAFF 16060 bytes
SHA-256: 5b0d2701ab39d2f69c66d7d16c60d8db0b323aa0832947137e757b5401d27330