Malicious PDF — malware analysis report

Static analysis result for SHA-256 b13bf20d7e180d1e…

MALICIOUS

PDF

81.4 KB Created: 2021-09-22 10:55:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 4c0f4fd7145a304f693c4fe2122fd12b SHA-1: 711fc44b763ef31d0c84b31962a7bfe85a6e4470 SHA-256: b13bf20d7e180d1e739999ef1c798195bb9fcfe816a65d17bfaf96405aa2cde5
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous links, many pointing to compromised or disposable domains, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery. While no scripts were extracted, the structure and URL analysis point towards a malicious document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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 http://elsped.hu/files/file/ruligagegep.pdf In PDF document text
    • https://kokomanis.com/contents/files/jofaxukowujisoro.pdfIn PDF document text
    • http://www.vandiestbrandstoffen.be/uploads/files/25021960295.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16145ab6bd6c8c---61946961355.pdfIn PDF document text
    • http://klick-tipp.info/ckfinder/userfiles/publics/files/638622452.pdfIn PDF document text
    • https://liur-krd.ru/userfiles/file/10987224310.pdfIn PDF document text
    • http://simp-q.ru/userfiles/file/naputurosinonajipi.pdfIn PDF document text
    • http://humanlitech.com/files/files/2262435610.pdfIn PDF document text
    • http://tochuchoinghi.org/files/39423935593.pdfIn PDF document text
    • https://imotrading.com/images/userfiles/posus.pdfIn PDF document text
    • https://angkaganjil.com/contents/files/23881597923.pdfIn PDF document text
    • http://www.octopus-quatuorvocal.com/ckfinder/userfiles/files/pitev.pdfIn PDF document text
    • https://ohligschlaeger-berger.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613e0f9ef4166---74103606865.pdfIn PDF document text
    • https://www.verpoort-bouw.be/wp-content/plugins/formcraft/file-upload/server/content/files/16133c1ea0cb96---41458722528.pdfIn PDF document text
    • https://tolgyesvolgy.hu/userfiles/file/84251657244.pdfIn PDF document text
    • http://marymo.ru/uploads/files/28446366872.pdfIn PDF document text
    • http://ambulatorioveterinariomariani.it/userfiles/files/99511888726.pdfIn PDF document text
    • http://jawarakreasi.com/file/64258397893.pdfIn PDF document text
    • https://norservis.cz/files/files/80892825424.pdfIn PDF document text
    • http://www.tlo.ntou.edu.tw/ckfinder/userfiles/files/pazifaketunamadude.pdfIn PDF document text
    • http://wang023spa.com/userfiles/202109file/2021090905010270554.pdfIn PDF document text
    • https://kaptenhoki.info/contents/files/67916457079.pdfIn PDF document text
    • http://av72-reklama.ru/userfiles/file/1631362647c28169d15cca0cb3bbc7.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=extreme+driving+simulatorPDF 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_off0000d975.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD975 17556 bytes
SHA-256: 3b4f6d62d7853b3fe0d9c861646ce22547c9f63fb17061549d742ce508fbb5e2
font_01_sfnt_off0001072a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1072A 10844 bytes
SHA-256: 9239aa8d065421be3ad73d0896c8c0ccf9d83692f67444010e4cc3018105a71b
font_02_sfnt_off00012004.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12004 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1