Malicious PDF — malware analysis report

Static analysis result for SHA-256 99562e03b76b7aad…

MALICIOUS

PDF

90.2 KB Created: 2021-06-30 14:32:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: ff40993e984aa4ddcb2e925d9fbf4938 SHA-1: 05ea03185a995aeb8999556fd61496c21b08b102 SHA-256: 99562e03b76b7aad217020c5c7177b521a539cdca72da832cbe06a681501aefc
156 Risk Score

Malware Insights

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

The sample was detected by ClamAV as Pdf.Phishing.Trojan and flagged by an ML classifier, indicating malicious intent. It contains a link farm pointing to multiple compromised CMS upload locations and disposable hosting domains, suggesting it's designed to redirect users to malicious content. The presence of numerous unknown URLs further supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

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 http://belgium-ex.com/images/blog//file/xaxipo.pdf In PDF document text
    • https://skazkavdom.com/wp-content/plugins/super-forms/uploads/php/files/865dd65a99c7d64b00c37542dcbbc609/bomanogolajof.pdfIn PDF document text
    • http://dok-vo.ru/userfiles/file/82340579242.pdfIn PDF document text
    • https://backcountryplayground.com/wp-content/plugins/super-forms/uploads/php/files/4cdce188e9a42d831228a0fbd7bc14cc/jisoguvive.pdfIn PDF document text
    • http://fixmyhelicopter.com/project-new/christianbook/upload_images/file/73191978258.pdfIn PDF document text
    • http://ahs1968.com/clients/d/dc/dcea35c349c70fb55dca458fc6558ff6/File/sazafekudu.pdfIn PDF document text
    • https://doellefjelde-mussemarked.dk/images/newsmail/file/4296343697.pdfIn PDF document text
    • http://mesterek.net/tmp/xepazumepiponemizizug.pdfIn PDF document text
    • https://plumcourse.com/wp-content/plugins/super-forms/uploads/php/files/9801bd6db5d5ba3d9a69e0e6fd1ecd5f/kojixenederiwaxisigitigad.pdfIn PDF document text
    • https://capitalsyndic.com/userfiles/file/85375947438.pdfIn PDF document text
    • https://adm.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/4d3134a0e0b58b84fc34d8bbb909001f/66219511050.pdfIn PDF document text
    • https://adasms.fr/userfiles/file/wedotubitaxabepem.pdfIn PDF document text
    • http://electrogalicia.com/electrogalicia/recursos/archivos/bexoxugapupagabobes.pdfIn PDF document text
    • https://hsegroup.ru/wp-content/plugins/super-forms/uploads/php/files/u7qtl20jvh6mh32i2jh799lhr3/runeluvijugavetapijew.pdfIn PDF document text
    • http://bascobrunswick.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160a79d550cfeb---3763615930.pdfIn PDF document text
    • https://www.enterpriselighting.com/wp-content/plugins/super-forms/uploads/php/files/1066d4adcd2e59677bff22f474e885bf/gamazofifutitinofuxifum.pdfIn PDF document text
    • http://incucinaconalberta.com/userfiles/files/44971784536.pdfIn PDF document text
    • https://storage-in-motion.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f1a2b9ce40---50987611336.pdfIn PDF document text
    • http://cargo3030.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1606f52fb33cc4---20123491772.pdfIn PDF document text
    • https://action-roofing.com/wp-content/plugins/super-forms/uploads/php/files/b938abb6b42057011ee0833ecab02544/72125841974.pdfIn PDF document text
    • http://nacyc.jp/Upload/file/jolemexajufulovimela.pdfIn PDF document text
    • https://regalcabs.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160bfec34f2804---74490673261.pdfIn PDF document text
    • https://purebodycare.courses/wp-content/plugins/super-forms/uploads/php/files/8dv9brlmfpdhfn89t76p0fd7f9/64229012106.pdfIn PDF document text
    • https://retentionstudentexperience.com/wp-content/plugins/formcraft/file-upload/server/content/files/160dbf22a6ed78---lazoja.pdfIn PDF document text
    • https://brusroom.com/wp-content/plugins/super-forms/uploads/php/files/fee49db208d7bb7f18ef814a49b719cb/mulepuzi.pdfIn PDF document text
    • https://www.couleurs-et-jardin.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160774d3868cf1---buzimiluredoxovitonuvo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=chi+square+test+two+variablesPDF 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_off0000f95a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF95A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00011171.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11171 10668 bytes
SHA-256: 0896b46b1305b2a0e039b57d1a585eaf03a3284a71e72237eac5a49f6865637d
font_02_sfnt_off00012a1c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12A1C 18408 bytes
SHA-256: 06c03e7a222f42a9529731250720cba208dd5d3931b87e027b417725f2c23042