Malicious PDF — malware analysis report

Static analysis result for SHA-256 b8e8f855891be49a…

MALICIOUS

PDF

78.1 KB Created: 2021-08-01 11:56:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: d7b31e3955fcd813f998ed8a2bdd4a36 SHA-1: fbb2389e8e1771f03a7a4fe22ca3a478e9df707a SHA-256: b8e8f855891be49a369325e7fb780d3c35e0c972676c7cc8f7a6a15cfe322959
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous external URIs and is described as a link farm, with many links pointing to compromised CMS upload storage or disposable hosting. The primary function appears to be directing users to potentially harmful external websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9853

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
  • 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 https://huntic.ru/uplcv?utm_term=manufactura+ingenier%C3%ADa+y+tecnolog%C3%ADa+kalpakjian+5+edici%C3%B3n PDF link annotation
    • http://ronaldtan.nl/images/photo/tulezezoxijosaguruxiwad.pdfIn PDF document text
    • http://przychodnia-felinskiego.pl/uploads/editor/file/lajugaxagi.pdfIn PDF document text
    • https://sonarmusic.hu/up_image/file/xenegezeninot.pdfIn PDF document text
    • http://fitviewer.de/files/file/vomolubef.pdfIn PDF document text
    • http://asirius.su/wp-content/plugins/super-forms/uploads/php/files/d03ee8a5dda56671beccc315ee09fce1/11754430844.pdfIn PDF document text
    • http://jointrilogy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac0aadef713---lazaxufubusizeruxemu.pdfIn PDF document text
    • http://www.yourhealthyourchoice.org/wp-content/plugins/formcraft/file-upload/server/content/files/160ace2b0e204e---50703632797.pdfIn PDF document text
    • https://sckstone.com/wp-content/plugins/super-forms/uploads/php/files/fe769f5a05677a89b4adb931933d431c/rimolawenuju.pdfIn PDF document text
    • http://canxetaidientu.com/images/file/gitasofopuriki.pdfIn PDF document text
    • https://habrit.tw/ckfinder/userfiles/files/saguxulipe.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ea6f44f591---22866032638.pdfIn PDF document text
    • http://www.lauricedale.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160a96e3887507---35053580336.pdfIn PDF document text
    • http://www.julitolaschools.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b7d5d5d083f---dezanitemibeder.pdfIn PDF document text
    • http://www.chicagoalphas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160832dadd5ae7---zopekes.pdfIn PDF document text
    • https://amitadevnani.com/userfiles/file/lejaduv.pdfIn PDF document text
    • https://londonvipchauffeur.co.uk/wp-content/plugins/super-forms/uploads/php/files/459d990216f3654cdabb9e014330c4d5/xefivavululumaju.pdfIn PDF document text
    • http://psychoterapia-przemysl.net/img/userfiles/file/sizefanebawudawepone.pdfIn PDF document text
    • https://www.tctnanotech.com/wp-content/plugins/super-forms/uploads/php/files/8a1d4afe0a39241ddfb1cfd40f627b90/45308173809.pdfIn PDF document text
    • http://lowry-averyreunion.com/clients/c/c0/c0e4e7922159a76f956c19110b7bfeb7/File/8002842790.pdfIn PDF document text
    • http://www.johnknox.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1607629c6bf230---fujolunidadareku.pdfIn PDF document text
    • https://www.paparazzirestaurant.com.au/wp-content/plugins/super-forms/uploads/php/files/21c950302daba8e51e0699fab28562c8/lomovu.pdfIn PDF document text
    • https://www.saammohaseb.ir/wp-content/plugins/super-forms/uploads/php/files/30836f300963aff370146bfd487ba309/dobesag.pdfIn PDF document text
    • https://www.avenueroadadvertising.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a8cce76f64---rofibozexofokata.pdfIn PDF document text
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/66cfe4d910070f5181d6b3fe9f040a41/bunasezozepadevedu.pdfIn PDF document text
    • http://bannermaul.com/userData/board/file/331882514.pdfIn PDF document text
    • http://krukewittfarms.com/userfiles/file/vekol.pdfIn PDF document text
    • http://amirafouad.com/uploaded_files/file/59830581278.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://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_off0000c818.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC818 17688 bytes
SHA-256: 33a41edbd822ebb3df1156a5ab2e521dd763ab6aa1f4061177bf2fa889bb0010
font_01_sfnt_off0000f512.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF512 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010d29.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D29 11388 bytes
SHA-256: f30134c70fcfa40b32cfae3968d93aef983a17412a6ec5e8d5b41bf8fae2ed80