Malicious PDF — malware analysis report

Static analysis result for SHA-256 db83f324018c1dac…

MALICIOUS

PDF

84.3 KB Created: 2021-09-13 10:16:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 8c016dc370254d8466175db67cb3b28c SHA-1: 688dcf2e294c332ddd5e7bde4384ff22401642a3 SHA-256: db83f324018c1dac8a6efd62a6e375c16897ee65e6d83c9eeded184660628ab8
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm, with multiple URLs pointing to potentially compromised or disposable hosting. The presence of embedded URLs and the nature of the link farm suggest an attempt to redirect users to malicious sites, likely for phishing or malware distribution. No scripts were extracted, but the PDF structure itself is used to host these links.

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://graveyards-fuj.ae/userfiles/files/97070639439.pdf In PDF document text
    • http://archiwum.wyryki.eu/admin/ckfinder/userfiles/files/tudenopepilodubun.pdfIn PDF document text
    • http://mikomisushiwc.com/uploads/files/3246423044.pdfIn PDF document text
    • http://deborahkay.com/ckfinder/userfiles/files/vumololipifigixere.pdfIn PDF document text
    • http://nano-vip.com/ckfinder/userfiles/files/12098278745.pdfIn PDF document text
    • http://chinajnbt.com/images/upload/File/52771083720.pdfIn PDF document text
    • http://www.viksexteriors.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132041f17494---70607064762.pdfIn PDF document text
    • https://pasarantogel2.com/contents/files/83934636680.pdfIn PDF document text
    • https://www.etbsupplies.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133b892b424b---44500905035.pdfIn PDF document text
    • https://yaslibakicisi.net/userfiles/file/89052015326.pdfIn PDF document text
    • http://xn--aknmedical-yub.com/uploads/file/pataxi.pdfIn PDF document text
    • http://alfavit.tv/userfiles/file/893571676.pdfIn PDF document text
    • http://ncfc.com.tr/ckfinder/userfiles/files/96307590637.pdfIn PDF document text
    • https://webgirls-studio.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136b686d68df---vobumazavenele.pdfIn PDF document text
    • https://1877painters.com/FCKeditor/file/dosetopotapenexukurejew.pdfIn PDF document text
    • http://opuspointpartners.com/ckfinder/userfiles/files/37561554845.pdfIn PDF document text
    • https://jlgardner.org/home/jlg/public_html/ckfinder/userfiles/files/wewupaw.pdfIn PDF document text
    • http://trust-law-firm.com/userfiles/file/20210906203458_196230976.pdfIn PDF document text
    • http://lasfyy.com/uploadfile/file/20210903093415635.pdfIn PDF document text
    • https://smartech.lv/sites/smartech/uploads/documents/files/51886633771.pdfIn PDF document text
    • https://vinaconexmec.vn/uploads/news_file/41794272508.pdfIn PDF document text
    • http://bilmatbasim.com/userfiles/file/7434240198.pdfIn PDF document text
    • http://files.ibiza-ferien.de/file/tugejagexo.pdfIn PDF document text
    • http://teaterskolen-efteruddannelsen.dk/ckfinder/userfiles/files/lijej.pdfIn PDF document text
    • https://nmcs.ca/userfiles/files/9897970317.pdfIn PDF document text
    • https://casabresciani.it/uploads/file/xukomumebididaga.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=how+can+i+get+into+someones+snapchatPDF 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_off0000e3f2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE3F2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fc09.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC09 10752 bytes
SHA-256: 14332a04ff2b0257a69ea249572e94eefff83ebd1a3b97ab9135d2acf8ff07b5
font_02_sfnt_off0001149c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1149C 17668 bytes
SHA-256: dc4e5e077904e63fd6fe1218201ed5999dfe210d66fecd42c5529a366cf2a077