Malicious PDF — malware analysis report

Static analysis result for SHA-256 a8ff3b319df6f8ff…

MALICIOUS

PDF

94.0 KB Created: 2021-05-18 08:53:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-24
MD5: d0b6e9c3e848b6f277b11740dda372f8 SHA-1: 190d179143217e4be758d9144f8e86c34f1929e5 SHA-256: a8ff3b319df6f8fffe99d2a73efdbbfc06e771a74011934ac8f0666df2b68689
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, indicating it functions as a link farm. The heuristic 'PDF_SEO_LINK_FARM' and 'PDF_SEO_DISPOSABLE_LINK_FARM' strongly suggest this behavior, with one URL pointing to 'https://maypoin.ru/strik'. While no scripts were explicitly extracted, the presence of numerous external links and the ML classification indicate malicious intent, likely for phishing or SEO spam.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://maypoin.ru/strik?utm_term=libro+de+los+suenos+significado PDF link annotation
    • http://ratebekanolaja.22web.org/75722176832.pdfIn PDF document text
    • https://jevilorusijugif.weebly.com/uploads/1/3/0/8/130874204/366b7f.pdfIn PDF document text
    • http://betuvunexe.22web.org/55720095593.pdfIn PDF document text
    • https://nitowapesapu.weebly.com/uploads/1/3/4/4/134442046/410709b60.pdfIn PDF document text
    • https://bategasef.weebly.com/uploads/1/3/2/7/132712490/fekekufixaj.pdfIn PDF document text
    • https://zadiletewus.weebly.com/uploads/1/3/4/5/134522124/pupifala-refudigimibag-labelovak.pdfIn PDF document text
    • https://fexasesari.weebly.com/uploads/1/3/1/0/131070539/0cd4d5cf14c2.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://pivukezafubajeg.rf.gd/business_process_management_and_outsourcing.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b8e8b043-6b8d-4f54-8e8f-50339fefaec3/91808409285.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/dd8e9f98-ab92-4db3-8c22-f00b375e9b5e/tusalenixuto.pdfIn PDF document text
    • https://s3.amazonaws.com/zusevamasor/adding_y_suffix_worksheet.pdfIn PDF document text
    • https://s3.amazonaws.com/rudelazifizuvo/wuluzevafasipevefowi.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9728728c-e903-45f8-b3d2-f12de5aa4d99/how_many_calories_in_a_small_dunkin_donuts_frozen_coffee.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4cf584db-29dd-469b-9dd5-ba7b51bcee7a/how_to_figure_out_how_many_grams_of_an_element_are_in_a_compound.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8f48db85-d45f-4704-8b41-62fa7fbfd422/39506629239.pdfIn PDF document text
    • http://rogadeza.epizy.com/93198023867.pdfIn PDF document text
    • http://wumevejuraluxe.rf.gd/nationalism_theory.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d5fb8127-9625-4c29-af69-79f60d80f824/wavobekekukinafuke.pdfIn PDF document text
    • https://s3.amazonaws.com/datarofapakil/vivujikuvog.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3015c1b9-2322-4051-b532-015d79ad762c/nurixusab.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/21be6bb6-e923-498e-a571-e490950a1e50/que_tipos_de_organizadores_graficos_hay.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

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00012ff3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12FF3 5268 bytes
SHA-256: bbd9edbbd3d1a89e46588f534378b05d6b56057ca7df0ca258064f8bc5d8f41c
font_01_sfnt_off000141f4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x141F4 12156 bytes
SHA-256: 7a4a686118f53bdded74f14b9319cff53561b376f773b2d9632627a5a048394f