Malicious PDF — malware analysis report

Static analysis result for SHA-256 164c1b13b545fde2…

MALICIOUS

PDF

87.1 KB Created: 2021-07-13 21:31:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: c313bfbc1eee334c1e4473bbf702b894 SHA-1: 093040d20a8c11ed2e410dfa1df34aa9caef7d60 SHA-256: 164c1b13b545fde281ebc50c1a84496b838d686c1e8a9a0d3acea94030e2f6fc
156 Risk Score

Malware Insights

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

The sample was detected by ClamAV as Pdf.Phishing.Trojan and flagged by an ML classifier, indicating malicious intent. It functions as a link farm, directing users to multiple compromised WordPress upload storage locations and disposable hosting sites. The primary goal appears to be directing users to external, potentially malicious, URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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
  • 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://pantryscan.com/123cars/imagefck/file/84354193353.pdf In PDF document text
    • http://wujipacking.tw/upload/files/lanilereruzomazonoj.pdfIn PDF document text
    • https://fastcomputer.vn/wp-content/plugins/super-forms/uploads/php/files/2891b15441489074d9b49207e4974280/84313783178.pdfIn PDF document text
    • http://kstarsmall.net/userfiles/file///76912674501.pdfIn PDF document text
    • http://slp70.com/clients/873855/File/34316421755.pdfIn PDF document text
    • https://nam.it/wp-content/plugins/formcraft/file-upload/server/content/files/1608c0943db90c---23824574759.pdfIn PDF document text
    • http://www.scmphotography.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160a57b1fa7120---4976045397.pdfIn PDF document text
    • https://tortugafilms.ca/adminfiles/file/vomerufawixiforeb.pdfIn PDF document text
    • https://apoiotelecom.com/imagens/img_fckeditor/file/bixogesosejujijabebu.pdfIn PDF document text
    • https://gaseg.com/wp-content/plugins/super-forms/uploads/php/files/pucv3bj2i3if5oqjbrrljsm3sa/babine.pdfIn PDF document text
    • https://smarttactic.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160e3ed86cddba---lamalagoju.pdfIn PDF document text
    • https://aprilboya.com/userfiles/file/19504562487.pdfIn PDF document text
    • https://alnahamgroup.com/userfiles/file/43929821231.pdfIn PDF document text
    • https://tipresentoio.it/images/file/25440767706.pdfIn PDF document text
    • https://heritagelogs.com/wp-content/plugins/super-forms/uploads/php/files/c59mb2augoejk7l1a7sbqs230m/dutoxiri.pdfIn PDF document text
    • https://www.prestigeautobody.com.au/wp-content/plugins/super-forms/uploads/php/files/6a73191dd4163b0debbb2bf793ef4d92/49611314188.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160c92130c2951---piliteketotawaz.pdfIn PDF document text
    • https://spencershaulageltd.co.uk/wp-content/plugins/super-forms/uploads/php/files/8a96a9434b261fa194fb3b1dfbd87e81/bopadigobokig.pdfIn PDF document text
    • https://noddy.nu/images/file/babidu.pdfIn PDF document text
    • https://burmesecatclub.nz/wp-content/plugins/super-forms/uploads/php/files/1da61dd77cc429b800205f91c010bc68/boputa.pdfIn PDF document text
    • http://akbmodel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608483b795fcf---71009447060.pdfIn PDF document text
    • https://canadianrelocation.net/wp-content/plugins/formcraft/file-upload/server/content/files/1608a846aa5717---disamag.pdfIn PDF document text
    • https://glosunspa.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609670f39e4ea---podigugubasoputepelofiwod.pdfIn PDF document text
    • https://benchmarktransitions.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cb71cac3d1---65429306847.pdfIn PDF document text
    • https://www.helpagesl.org/wp-content/plugins/formcraft/file-upload/server/content/files/1608fa32e060d2---lufafijejijomerexazugemu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=my+treat+meaningPDF 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_off0000f322.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF322 17448 bytes
SHA-256: 7671ad0841f0c4b5d89bce77483a2aca1907ca3154fec585e65a22a9701ef6c0
font_01_sfnt_off000120c7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x120C7 10224 bytes
SHA-256: 7fc575c806eee15c51a48e44767eb36962dd7b5da2417106a4597bc75d9276c2
font_02_sfnt_off000137b4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x137B4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1