Malicious PDF — malware analysis report

Static analysis result for SHA-256 de511089a56121f7…

MALICIOUS

PDF

82.6 KB Created: 2021-09-21 01:59:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 892e50f905afb098f525780401bc4f85 SHA-1: 5d81c957e9c614737518ce39eae5e6ee933439b3 SHA-256: de511089a56121f791ee4e3ac43a434a84ab1387323eb4d21a455a348bbc12b7
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF was flagged by ML classifiers and ClamAV as malicious. It contains numerous embedded URLs, many of which point to PDF files hosted on distinct domains, indicating a link farm. One heuristic specifically identified it as a 'PDF_SEO_DISPOSABLE_LINK_FARM', suggesting a malicious intent related to search engine optimization or distributing further malicious content. No scripts were extracted, and the document body was unreadable binary data.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://vandolderskb.com/images/usr/tomezedukokifurevapesela.pdf In PDF document text
    • http://feldbach-tourismus.at/files/venumefikuduzewakuwena.pdfIn PDF document text
    • http://jingluo.net/uploadfiles/files/xapodapif.pdfIn PDF document text
    • http://meimagedance.tw/ufiles/files/teponalesilegokuvinov.pdfIn PDF document text
    • http://elitacasa.it/images/file/giruxojefavu.pdfIn PDF document text
    • http://shceping.com/upFile/photos/2021-9/file/pufebikomarevot.pdfIn PDF document text
    • https://hobbyschuurtje-webwinkel.be/images/userfiles/file/70121350243.pdfIn PDF document text
    • http://vegman-kzn.com/ckfinder/userfiles/files/fabafivegefuruxe.pdfIn PDF document text
    • https://verredistri.fr/xmedia/file/lamub.pdfIn PDF document text
    • http://hermanosgolbano.com/admin/fckeditor/editor/filemanager/connectors/phpfile/80393811742.pdfIn PDF document text
    • http://bladensburg.abwingsmd.com/uploads/files/83438906369.pdfIn PDF document text
    • http://vattucongtrinh.com/userfiles/file/gosogurejebivililurokifa.pdfIn PDF document text
    • http://tainanrup.longi.tw/uploadfiles/files/20210917_015932_7943.pdfIn PDF document text
    • https://candbco.com/ckfinder/userfiles/files/bokefozotob.pdfIn PDF document text
    • https://www.displaysdirectaustralia.com.au/application/third_party/ckfinder/userfiles/files/mofisaxu.pdfIn PDF document text
    • https://na-nule.ru/wp-content/plugins/super-forms/uploads/php/files/2a3k6olts0hvanpoks6ik27677/80285933774.pdfIn PDF document text
    • http://unipsyclinic.com/userfiles/file/20210902211409.pdfIn PDF document text
    • http://erbaytag.com/resimler/files/puvov.pdfIn PDF document text
    • https://oncallanatomist.com/ckfinder/userfiles/files/nukapefibamaletejuvoworeg.pdfIn PDF document text
    • http://trust-law-firm.com/userfiles/file/20210910040711_954626975.pdfIn PDF document text
    • http://rosesrealtyhomes.com/userfiles/files/1581136507.pdfIn PDF document text
    • https://protectname.xyz/whoisprivacy/userfiles/files/galusawibubu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=how+to+download+movies+with+subtitles+using+utorrent+on+androidPDF 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_off0000dbeb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBEB 11080 bytes
SHA-256: 3bc5043b563c07fe6d6d99d49bb3f48b32c4774c8158b8ac30dcf06f54f66d64
font_01_sfnt_off0000f54d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF54D 17372 bytes
SHA-256: 8ce9ec71f4059e505cccc43f4b259a576209fd07ed177425c69e65455470dfa5
font_02_sfnt_off00012224.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12224 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1