Malicious PDF — malware analysis report

Static analysis result for SHA-256 961a1bd27c37d3cf…

MALICIOUS

PDF

81.1 KB Created: 2021-09-22 11:17:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: d7841c10f745e8957673386daafaac69 SHA-1: 358ae6ca1a8ab2c3078208d5e3768bd8bd49df30 SHA-256: 961a1bd27c37d3cf8e2e512531ca7cda6d86d9735b4c17f6a33243067cb117c1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier. It contains numerous external URIs and link farms hosted on potentially compromised or disposable domains, suggesting a phishing or malware distribution lure. The presence of embedded URLs and the nature of the heuristics indicate that the primary goal is to redirect the user to malicious websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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=mt+manager+apk+download PDF link annotation
    • http://lnv-cnc.gr/userfiles/file/mubajesuvozezazego.pdfIn PDF document text
    • http://wohntraumgmbh.at/gabutanalo.pdfIn PDF document text
    • http://style4.allwebeasy.com/userfiles/files/88328407145.pdfIn PDF document text
    • http://uni-farm.pl/ckfinder/userfiles/files/35370147185.pdfIn PDF document text
    • https://nbcmedia.vn/ckfinder/userfiles/files/rozitaliba.pdfIn PDF document text
    • http://www.commandinglife.com/wp-content/plugins/formcraft/file-upload/server/content/files/161408da7355de---nanuzifunezizenakejezu.pdfIn PDF document text
    • https://imapcb.org/wp-content/plugins/super-forms/uploads/php/files/e0dee4e1bbeb5b3db9a5ab8d79b063a0/vikipojuva.pdfIn PDF document text
    • https://xn--80aaijz0c.xn--p1ai/ckfinder/userfiles/files/97773034090.pdfIn PDF document text
    • http://gemaeldeundobjekte.de/uploads/files/50653024872.pdfIn PDF document text
    • http://prplus4u.com/ckupload/files/67950662059.pdfIn PDF document text
    • http://www.sandipmallick.com/fckimages/file/bodomerutetametixe.pdfIn PDF document text
    • http://ersenergy.com/UserFiles/file/sanuxoxijotaxojesunojiliz.pdfIn PDF document text
    • https://www.pactforfamilies.org/ckfinder/userfiles/files/64528268772.pdfIn PDF document text
    • http://eco-building.cz/UserFiles/File/71925398929.pdfIn PDF document text
    • https://24emk.ru/ckfinder/userfiles/files/29024358959.pdfIn PDF document text
    • http://gbfrjournal.org/pds/userfiles/files/68216642745.pdfIn PDF document text
    • http://www.oomedia.com.tw/ckfinder/userfiles/files/19231179061.pdfIn PDF document text
    • https://unosms.us/userfiles/file/30815857224.pdfIn PDF document text
    • https://polinagerz.ru/wp-content/plugins/super-forms/uploads/php/files/nbvb3v5r6g516aufvlbk4cate3/kumajitisiro.pdfIn PDF document text
    • https://www.grandeprairie.org/wp-content/plugins/formcraft/file-upload/server/content/files/16130218e9796f---tumiwepetikoj.pdfIn PDF document text
    • http://szsahsh.com/uploads/files/zisidetevi.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_off0000da21.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA21 17240 bytes
SHA-256: 00a82fe55af8c6375de6214f1c7221dd46e4e0526989d7abbdbcd614ca537bff
font_01_sfnt_off000106d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106D6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011eed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11EED 10648 bytes
SHA-256: 7f1f68d5f675ef46c78bf44646f0c7dde5dd4f26af64a9d04d51c0421231d235