Malicious PDF — malware analysis report

Static analysis result for SHA-256 31467984f36d9a57…

MALICIOUS

PDF

82.1 KB Created: 2021-09-01 08:13:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: da8b5a5df95ea7f41b71ca7a579770f7 SHA-1: cc59c3e82bf21fd647e5de42003413ea311bebfc SHA-256: 31467984f36d9a5737895386d369d098877b72c85d5ef0c2615580e6172777b0
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The sample is a PDF file flagged by ClamAV as a phishing trojan and by an ML classifier as malicious. It contains numerous links, many pointing to compromised WordPress sites and disposable hosting, suggesting a link farm designed to redirect users. The PDF's structure and embedded links indicate it's intended to lead users to malicious content, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9944

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://hylyt.co/wp-content/plugins/super-forms/uploads/php/files/3fc2fe8efcade6329bdf90b30939ea1a/jajogapasep.pdf In PDF document text
    • https://amursvoidom.ru/media/files/xibinerajusipigovono.pdfIn PDF document text
    • http://brkvinc.com/userfiles/file/tudafakula.pdfIn PDF document text
    • http://moffatcountyhighschool65.com/clients/878592/File/60817905677.pdfIn PDF document text
    • http://clinicaveterinariacene.com/userfiles/files/46535427875.pdfIn PDF document text
    • https://fablab808.com/nbloom/fckuploads/file/bitewuzi.pdfIn PDF document text
    • https://ilexgold.com/app/webroot/files/userfiles/files/83691617528.pdfIn PDF document text
    • https://www.kiteschule-kiel.de/wp-content/plugins/formcraft/file-upload/server/content/files/16089e3605f0e6---geluwajamemivebepugo.pdfIn PDF document text
    • http://solarissoft.com/img/userfiles/files/lidopepimuz.pdfIn PDF document text
    • https://journalofcritique.com/ckdosyalari/upload/files/pibeduketamikozow.pdfIn PDF document text
    • http://www.bc-arman.kz/ckfinder/userfiles/files/99643531440.pdfIn PDF document text
    • http://azs-szermierka.pl/zdjecia/fck/file/matolokere.pdfIn PDF document text
    • http://abnicum.com/files/file/lodute.pdfIn PDF document text
    • http://doubles301.jp/files/ckeditor/files/savewuduzulemivo.pdfIn PDF document text
    • http://cameradungphat.com/uploads/files/sudipamosixinegiwafuxod.pdfIn PDF document text
    • http://teaterskolen-efteruddannelsen.dk/ckfinder/userfiles/files/97161870182.pdfIn PDF document text
    • https://advicezone.org.uk/wp-content/plugins/super-forms/uploads/php/files/hh8eb7s8ctln0n59759r28rb7n/89169439354.pdfIn PDF document text
    • https://stakeoutllc.com/wp-content/plugins/super-forms/uploads/php/files/bc8750daae404435ee02b2ba250c8ee8/gitepebadedugew.pdfIn PDF document text
    • http://www.ncstarim.com.tr/wp-content/plugins/super-forms/uploads/php/files/mbkpkgdjfcdrh57ql5mqp3flk7/135076371.pdfIn PDF document text
    • http://osc-pribor.ru/products_pictures/file/xulumidew.pdfIn PDF document text
    • https://digireg.lu/upload/66823476381.pdfIn PDF document text
    • https://www.baust.edu.bd/app/webroot/ckfinder/userfiles/files/22214079083.pdfIn PDF document text
    • https://casabresciani.it/uploads/file/zaruguwanatunemef.pdfIn PDF document text
    • http://woonhuislift.info/wp-content/plugins/formcraft/file-upload/server/content/files/1606c892b30969---bojelatolesirijafuvarodos.pdfIn PDF document text
    • http://teplospectr.ru/images/files/xolewaravasiguwupowedusor.pdfIn PDF document text
    • https://signika.pl/Upload/file/98623571730.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=dow+futures+this+morningPDF link annotation
    • 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_off0000d6a9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD6A9 18948 bytes
SHA-256: e345ca7e1fa9e5303d8f4924f5b776eaceda9c517f6273cdf29be641ed910c9c
font_01_sfnt_off00010828.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10828 10640 bytes
SHA-256: 092709e6ae9cca0fa8474f8c666662a70b62ab88b5efd575fb96503081cde554
font_02_sfnt_off0001206c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1206C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1