Malicious PDF — malware analysis report

Static analysis result for SHA-256 f8fd61dadea0dffd…

MALICIOUS

PDF

91.6 KB Created: 2021-06-28 00:31:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 1507f74c8013d2874640e2b5171a23b5 SHA-1: 60ec13f4937681bf1f71bc83131284c9964b1bb8 SHA-256: f8fd61dadea0dffd20934bdb046b723f00403281908ce13d6a779a3057a9e272
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links to external websites, many hosted on compromised WordPress installations or disposable domains, suggesting a link farm or phishing lure. The presence of PDF-specific heuristics like 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' reinforces this assessment.

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 https://medvor.ru/uplcv?utm_term=how+to+in+text+cite+a+paragraph
    • http://polipadel.com/userfiles/file/sivofofofubatat.pdf
    • http://mineraux-et-lithotherapie.fr/ckeditor/upload/files/falususoxonerenejo.pdf
    • https://parisautotravel.com/wp-content/plugins/super-forms/uploads/php/files/ggilijjohl7ujksbdatd5o6vr4/10131032960.pdf
    • https://na-nule.ru/wp-content/plugins/super-forms/uploads/php/files/8vguioonbdlb5k7rpur7ti4l04/49793882410.pdf
    • http://kaztelcom.kz/ckfinder/userfiles/files/24541101449.pdf
    • http://xiaohecollege.com/d/files/55074359492.pdf
    • https://annjulieskarpmo.com/userfiles/file/4724484215.pdf
    • http://queuemanagementsystems.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c8a905ec52e---79085786932.pdf
    • https://amblamy.ee/upload/file/muvofaz.pdf
    • https://www.ideaklinikkadikoy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608d31a861d2f---vixigimetamalevososijemop.pdf
    • http://zgkimsteszew.pl/img/upload/files/2367099423.pdf
    • http://physocare.com/Images_upload/files/takagataritinebipexi.pdf
    • http://bethtikvahevents.ca/clients/2/20/20a91c0cb94b02964b0d1c5d980f1596/File/rofevilavuzizadis.pdf
    • https://extremetour74.ru/wp-content/plugins/super-forms/uploads/php/files/ff56a72839e1ff4d02861bbad4731b24/zusigifew.pdf
    • https://polskieplytki.com/wp-content/plugins/super-forms/uploads/php/files/407d4b028a72c9de489cc3a0369136d5/16398436109.pdf
    • http://kath-kiga-bw.de/bilder/berichte/file/wozuje.pdf
    • http://kolesnikov.pro/ckfinder/userfiles/files/55469715219.pdf
    • https://wacee.net/wp-content/plugins/formcraft/file-upload/server/content/files/16084c9e0f093d---85437256198.pdf
    • https://www.federatedlighting.com/wp-content/plugins/super-forms/uploads/php/files/b3b2b70dec7cd5c6e5e2505c0316b7de/kufekoroviremu.pdf
    • https://smarttactic.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1608265d79efc2---65645005293.pdf
    • https://gpagroup.in/wp-content/plugins/formcraft/file-upload/server/content/files/1607b11a7bb9f3---20867676497.pdf
    • https://alphacleanwashing.com/wp-content/plugins/super-forms/uploads/php/files/68ebcb2e072b9ee6f91312d539f79081/48208877773.pdf
    • https://www.criteriainvest.com.br/wp-content/plugins/super-forms/uploads/php/files/pl8cums1k0a6ir4446qjqthdqr/rojozemavowirotilalotibel.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000103bb.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x103BB 16792 bytes
font_01_sfnt_off00011bcd.bin
23db01a735eae54473afe84ecc5ffb82811265d8a9530a1f9b71286022a2f0af
pdf-font-stream PDF embedded font (sfnt) at offset 0x11BCD 17296 bytes
font_02_sfnt_off000148f0.bin
472130862a64765a6672ab4fcad23bfd7b368f450234c346a55123ccf3347f77
pdf-font-stream PDF embedded font (sfnt) at offset 0x148F0 10620 bytes