Malicious PDF — malware analysis report

Static analysis result for SHA-256 a957e44c9ad978fc…

MALICIOUS

PDF

74.1 KB Created: 2021-10-08 01:54:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 6a418ea001be342fa070875faac252bf SHA-1: 8bcd9e2a6a76431a1cb021b70e34e185d9a1b578 SHA-256: a957e44c9ad978fc200d2f0a4268e05793806c65568d116e5e7558d485befdbf
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous links, many of which point to compromised WordPress sites, suggesting a link farm or phishing lure. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were directly extracted, the PDF structure and embedded URLs are indicative of a phishing or redirection attack, likely delivered as a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://www.inter-tube.co.uk/wp-content/plugins/super-forms/uploads/php/files/5b3e9e85dbd49ba8528522b6e5414164/nupesadomalunanufomu.pdf In PDF document text
    • http://tentauto23.ru/ckfinder/userfiles/files/24513638627.pdfIn PDF document text
    • https://insolite.lu/img/userfiles/files/jebafuvesaguvolugataneb.pdfIn PDF document text
    • https://learningsolution.ca/userfiles/files/78302014968.pdfIn PDF document text
    • https://hanurichurch.org/ckfinder/userfiles/files/monorafavopelo.pdfIn PDF document text
    • http://lynxauto.ru/userfiles/file/63222617450.pdfIn PDF document text
    • http://lotusromeo.fr/app/webroot/files/userfiles/files/98003561497.pdfIn PDF document text
    • http://tuvanthanhlapcongty.biz/upload/ck/files/wuxonuzamefofetarijodu.pdfIn PDF document text
    • http://mixmarketing.vn/upload/fck/file/kawupojazuzaj.pdfIn PDF document text
    • https://jdrum-music.com/uploads/ckfiles/files/59714691837.pdfIn PDF document text
    • http://xn--b1akwe.xn--p1ai/userfiles/file/fodutebutirukeka.pdfIn PDF document text
    • http://localhomesales.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16155cf1fec627---wanelodawojelufizirujasaz.pdfIn PDF document text
    • https://www.lenoir-elec.com/wp-content/plugins/super-forms/uploads/php/files/8ohpglh8v4fh022i08lvnerfri/78977284916.pdfIn PDF document text
    • http://lightofislamonair.org/uploads/files/puseburamejowuvofa.pdfIn PDF document text
    • http://kolesnikov.pro/ckfinder/userfiles/files/31902458865.pdfIn PDF document text
    • https://west-holding.com/userfiles/file/41019859112.pdfIn PDF document text
    • https://ht-cooling-j3t.com/contents/files/27653295914.pdfIn PDF document text
    • http://banghetretruc.com/media/ftp/file/75733373446.pdfIn PDF document text
    • http://daydreamspin.com/userfiles/file/56392934841.pdfIn PDF document text
    • http://lnv-cnc.gr/userfiles/file/razabovif.pdfIn PDF document text
    • http://kibunajcc.com/ckfinder/userfiles/files/wenewim.pdfIn PDF document text
    • http://lexxyin.net/files/fckeditor/file/livebomenowofuxe.pdfIn PDF document text
    • http://rockycheng.com/ckfinder/userfiles/files/nokifomedilujifina.pdfIn PDF document text
    • https://xehowo24h.com/images/ckeditor/files/sokajidewalox.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=national+center+for+biotechnology+informationPDF 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_off0000bfda.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBFDA 10848 bytes
SHA-256: 02bada877497168e2032ee49b04d815b59fefa4068ab17a3e3e1682c30c5036a
font_01_sfnt_off0000d8ba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8BA 16404 bytes
SHA-256: 15817043ef82feacb8297a54db8311cd50cd1547ebf1bf5643ec17ea0835fcc4
font_02_sfnt_off00010279.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10279 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1