Malicious PDF — malware analysis report

Static analysis result for SHA-256 53f514e90c0b1f08…

MALICIOUS

PDF

86.2 KB Created: 2021-08-13 11:22:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 0342334962dc3cf87f1c25ca002a04f6 SHA-1: e77d864442ff7e30f140e77586c7e5b0587d00ab SHA-256: 53f514e90c0b1f08e66d479b51a1115a1c224dc38228b2674ebca569b9f1ea79
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains numerous links to external websites, many hosted on compromised CMS platforms or disposable domains, suggesting a link farm or phishing lure. The ML classifier and ClamAV detection strongly indicate malicious intent. Although no scripts were explicitly extracted, the presence of external links and the nature of the heuristics point towards a phishing or malware distribution campaign, likely initiated via a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

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://archism.ru/uplcv?utm_term=how+to+repair+brass+carburetor+float PDF link annotation
    • https://www.skyline-recruiting.com/wp-content/plugins/super-forms/uploads/php/files/199d2c3ef964f31ff0b4e7f205dd1311/raxideve.pdfIn PDF document text
    • http://szpk.hu/_user/file/77146589768.pdfIn PDF document text
    • http://www.jindatunnel.com/up_files/file/55849231441.pdfIn PDF document text
    • http://catherine-massage.com/ckfinder/userfiles/files/92573960770.pdfIn PDF document text
    • https://lion-trading.co.uk/wp-content/plugins/super-forms/uploads/php/files/csc1sgjptpc4usdth5r7ekq66k/tumupulowudanukij.pdfIn PDF document text
    • https://alakharia.com/public_html/userfiles/file/fugipuxivulufoves.pdfIn PDF document text
    • http://funagamex.vn/PhuongNamGroup/userfiles/files/96414643662.pdfIn PDF document text
    • https://jdbailbonds.com/wp-content/plugins/super-forms/uploads/php/files/5757976bad7b82cc43886a7b489cc987/pijajamalukixutunikuke.pdfIn PDF document text
    • https://envida-nieuws.nl/bsb_website/upload_fck/file/nudenijiroximuj.pdfIn PDF document text
    • http://old.smartplus.pl/ckfinder/userfiles/files/5435970473.pdfIn PDF document text
    • https://cor.org.ar/wp-content/plugins/super-forms/uploads/php/files/ohvtm6e02tn4g7i53f4jfgv4h4/nosavugifi.pdfIn PDF document text
    • http://charivne.info/images/file/34209060999.pdfIn PDF document text
    • https://provisionsinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608b7206f3936---33300126496.pdfIn PDF document text
    • https://www.revistadefiesta.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080da71dc8db---81096321393.pdfIn PDF document text
    • http://eurekaelearning.com/upload/news/file/47847506864.pdfIn PDF document text
    • http://tsg-edinstvo.ru/userfiles/file/52434853786.pdfIn PDF document text
    • https://www.breastcancerfoundation.in/wp-content/plugins/super-forms/uploads/php/files/7aa4ad46f422d6dd29840c7dcef20ad3/zatatoviremijosolo.pdfIn PDF document text
    • https://motodubai.com/uploaded_images/files/91513155008.pdfIn PDF document text
    • https://www.medicalart.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16085b5ad555a0---bivafedatexu.pdfIn PDF document text
    • http://www.sunargrup.com.tr/wp-content/plugins/super-forms/uploads/php/files/im2iouapfnugcifujnerha7ub5/99856780778.pdfIn PDF document text
    • http://epicridesnepal.com/files/58925362734.pdfIn PDF document text
    • http://socialbomjesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b5e079ac70d---78847823667.pdfIn PDF document text
    • http://goref.ru/files/file/sixemobobuvekaketizetefa.pdfIn PDF document text
    • http://adamlegal.com/userfiles/file/61350480205.pdfIn PDF document text
    • http://medi-sen.com/files/files/1442095286.pdfIn PDF document text
    • http://studiomanzetti.it/userfiles/files/56803241904.pdfIn PDF document text
    • 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_off0000ef3d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF3D 16948 bytes
SHA-256: fe6137ff20b13d8e4ae8d5be4d777c1d36b45236174b035d6ba556cee67ff2a9
font_01_sfnt_off00011a38.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A38 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001324f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1324F 10684 bytes
SHA-256: aad22906689e75be5230e32fcad75f95902173f8e6bee2e51ddc8110a3560f90