Malicious PDF — malware analysis report

Static analysis result for SHA-256 72aa26e8b9248fd4…

MALICIOUS

PDF

78.5 KB Created: 2021-03-16 01:53:33 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: af31087a3ff9a95e7281d372a95d553a SHA-1: 57131c4e2d79eb8c58c040bfa62a80a1bbf22ddd SHA-256: 72aa26e8b9248fd419242eb3edade7f419a0a8e0e17a77c9362c2e5363475d2b
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many pointing to disposable domains, suggesting a link farm or SEO poisoning tactic. The ClamAV detection and ML classifier strongly indicate malicious intent, specifically identified as a phishing trojan. While no scripts were directly extracted, the PDF structure and numerous external URLs are indicative of a malicious document designed to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://resalured.ru/123?utm_term=apron+pdf+patterns+free PDF link annotation
    • http://art-practice.org/auld_lang_syne_piano_chords_for_beginnersm1ccc.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4484804/normal_604c9f7821886.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4366041/normal_60077577ee9fa.pdfIn PDF document text
    • http://idealica-italiaoficial.site/theocratic_ministry_school_software_macwxnpx.pdfIn PDF document text
    • http://vazitafolozif.22web.org/31012770695.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4414489/normal_6015aea516783.pdfIn PDF document text
    • http://momentikshop.space/vewemeremuza8982f.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/c5116fa5-f8e8-422d-930f-0039f3ff9562/38283181272.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6e5d35c8-0626-43ee-aa02-b36a130607f7/organic_chemistry_basic_notes_download.pdfIn PDF document text
    • https://0503187d-52cd-4237-9521-a3cb9bf551ae.filesusr.com/ugd/5bb01c_56e0c4476e62484e865841af794c6b8f.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/6f9ad5b5-58fe-4fa3-bf57-e78707c65450/rezujed.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0bbfc4a9-13ca-4770-bfe2-00983466e1b8/friedrich_nietzsche_beyond_good_and_evil_audiobook.pdfIn PDF document text
    • http://pijiwir.rf.gd/dizikokufisadakapetezixik.pdfIn PDF document text
    • https://e3e1c2aa-7f41-47b0-8c2f-d823cb48b857.filesusr.com/ugd/7598fa_f17411eed182414080df2aa5d14392f8.pdf?index=trueIn PDF document text
    • http://vatilibudavelit.rf.gd/penumbra_black_plague_full_game.pdfIn PDF document text
    • https://724418e0-3ace-43c1-abd8-628b4820fc71.filesusr.com/ugd/6df952_ada50927f5e54c8784a73c60b2e6c6d1.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/bc380e5c-90ae-419c-96b1-174f33453685/degoxabuxubajatewos.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5edadf56-7c48-468a-b364-f579e44fce31/zeliposixabodumidavagapos.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1748a130-97bb-464d-a659-015c0622ffbd/how_to_use_brother_p-touch_label_maker.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_off0000e078.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE078 4992 bytes
SHA-256: 809dfdd852c2f9f9d6a65802853eb53f49356d38c1e4d6684a3773553a57ae14
font_01_sfnt_off0000f185.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF185 11220 bytes
SHA-256: 0f115c663bf9ee409ec7f6c4100771286a43eb8c8421db62528fc12ec2da70e0
font_02_sfnt_off000117b3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x117B3 16204 bytes
SHA-256: a95eff378c135b1ab40d10b3cd1da1bafbc07f86005f57898d079c90d712ddbd