Malicious PDF — malware analysis report

Static analysis result for SHA-256 6878be86544ad208…

MALICIOUS

PDF

88.5 KB Created: 2021-05-27 22:29:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-15
MD5: a5cf076959c1bb7dc0847c0916ba2769 SHA-1: b3e96394cb2a28e4c5f5f2bdd0d233786a7dcf60 SHA-256: 6878be86544ad208daf37b217ab4809e9b78638702cd84bc358651b3eabc2236
186 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 hosted on disposable domains, suggesting a link farm designed to distribute traffic or host malicious content. The primary URL, 'https://dafemum.ru/strik?utm_term=barbell+medicine+the+bridge+3.+0+pdf+download', appears to be a lure for a document download, but redirects to this link farm. ClamAV and ML classifiers also identified this PDF as malicious, specifically as a phishing trojan.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://dafemum.ru/strik?utm_term=barbell+medicine+the+bridge+3.+0+pdf+download PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4374682/normal_60017f4cba892.pdfIn PDF document text
    • https://mozurizubomexaj.weebly.com/uploads/1/3/4/6/134643417/pukakesazuwowad_mewat.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4416932/normal_5fca7c8c01e76.pdfIn PDF document text
    • https://xanowiporak.weebly.com/uploads/1/3/0/8/130814060/30354459db7ed.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4480581/normal_606492218b2fc.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4393181/normal_605b9595d19b3.pdfIn PDF document text
    • https://zodukoweferu.weebly.com/uploads/1/3/1/0/131069906/jebuxud_poxubuteduzoxof_jilepinig.pdfIn PDF document text
    • https://tarivoda.weebly.com/uploads/1/3/4/6/134693378/sevuvubewujonefud.pdfIn PDF document text
    • https://juxepikipoz.weebly.com/uploads/1/3/4/4/134486641/915553.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4375206/normal_5fd170a6aa88c.pdfIn PDF document text
    • https://zenorawe.weebly.com/uploads/1/3/2/3/132303237/zokepiwewix-mulapolat-gigofilemu.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4451044/normal_5ffed33120892.pdfIn PDF document text
    • https://votaxejasusax.weebly.com/uploads/1/3/0/9/130969278/somusebez.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4416132/normal_5fe90b041a6e0.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4448536/normal_60695289767b0.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/89753ffc-c632-4357-950f-0a826a6dcbe9/how_to_pass_walmart_assessment_2020.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/de0ceaeb-1ccd-47b1-addb-7c1a6d701498/how_great_thou_art_sheet_music_chords.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/be9e4d39-dc7c-4ab7-b3b4-470ebf9a1bef/girinugemaneguduro.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/be0fb270-2bde-4c3d-808d-2660a6c07508/toxasanurelenopakuzujo.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c27af953-be1b-42d3-99ba-946d3281de56/south_carolina_drivers_manual_2021.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/35531e3a-5146-4bb9-9f70-d5f02763b41b/what_does_the_staff_in_young_goodman_brown_symbolize.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3f5d68f2-5dbf-4bf9-8cf7-cb3eecab4838/gta_san_andreas_cleo_gold_apk_free_download.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ead0d91c-602d-4950-85fc-9df8eb81a8b1/where_to_buy_big_buddy_heater.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_off000103f2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103F2 6008 bytes
SHA-256: d6134d6117bb789e0427a8ab9f86a04d5f2d619b0724c0e5869c66f6311e0125
font_01_sfnt_off0001184e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1184E 11256 bytes
SHA-256: ba3b4d48840161dd73ba9a2ff1ec90d52cfcae5787a6db92386037413d9f9dba
font_02_sfnt_off00013eef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13EEF 16164 bytes
SHA-256: 4b52fd5da643d9c08cc0a86f773b2f024e3274f3f861dfcac100db1ef433cf06