Malicious PDF — malware analysis report

Static analysis result for SHA-256 8619ccb83edc35cc…

MALICIOUS

PDF

81.4 KB Created: 2021-10-08 04:42:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-21
MD5: 8a2657637bed0f66a8b6db9742f382a2 SHA-1: 3ec6353ac662c3b6d35a6b05e4cffd6a650d4868 SHA-256: 8619ccb83edc35ccdf75d3421ece629c6632d41de5f70f0aed244babebf678f2
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF sample was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicates it functions as a link farm, directing users to numerous distinct hosts, likely for phishing or malware distribution. While no scripts were explicitly extracted, the presence of embedded URLs and the nature of the heuristics suggest an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9911

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 http://panyuchen.com/ckfinder/userfiles/site_eachfun_com/files/bamurugu.pdf In PDF document text
    • http://on-video.com/movies/movie_data/file/42454498253.pdfIn PDF document text
    • https://storycycle.com/ckfinder/userfiles/files/1367190679.pdfIn PDF document text
    • https://hps-gruppe.com/wp-content/plugins/super-forms/uploads/php/files/9mau0v4do4s965q8vgsho09qgr/tivitamepakutivon.pdfIn PDF document text
    • http://sm300159.agchost.com/userfiles/files/31609327760.pdfIn PDF document text
    • https://www.auto-ecole-rive-droite.fr/ckfinder/userfiles/files/liginozinuxateti.pdfIn PDF document text
    • http://alrabbancapital.com/file/files/mexulowu.pdfIn PDF document text
    • http://simonide.org/userfiles/file/72231782397.pdfIn PDF document text
    • http://hostingureitings.lv/uploads/userfiles/files/masusad.pdfIn PDF document text
    • http://drprdesaihospital.com/uploads/punejexogexiwuge.pdfIn PDF document text
    • http://kuwaited.com/cote_dor_import/admin/ckfinder/userfiles/files/26905245479.pdfIn PDF document text
    • https://monarchwinemerchants.com/wp-content/plugins/super-forms/uploads/php/files/e980b3c5163b34f51866dc3c6d83bf85/wezizibadubugilul.pdfIn PDF document text
    • http://www.insight-assessment.com/ckfinder/userfiles/files/45638478297.pdfIn PDF document text
    • http://bkdesign.ee/userfiles/file/tofuxitilikozagodoponeze.pdfIn PDF document text
    • http://happyhanool.com/ckupload/files/dulapezuleranujokobiwize.pdfIn PDF document text
    • http://xn--elementy-zczne-kwb98g.pl/media/file/pozasixilugaririk.pdfIn PDF document text
    • http://allgeology.ru/ckfinder/userfiles/files/35594754135.pdfIn PDF document text
    • https://apra.pl/files/file/77471951398.pdfIn PDF document text
    • https://ecpa.fr/uploaded/file/87034770876.pdfIn PDF document text
    • https://youkuvpn.com/upload/files/49637701963.pdfIn PDF document text
    • https://jecoexports.com/ckfinder/userfiles/files/37895167482.pdfIn PDF document text
    • https://ht-cooling-j3t.com/contents/files/pejewoxubutijer.pdfIn PDF document text
    • https://vialivonica.eu/userfiles/files/nileligasurivotixexebe.pdfIn PDF document text
    • http://vers-ma.de/userfiles/file/mogemenevivij.pdfIn PDF document text
    • http://yuanjen.com/ckfinder/userfiles/files/46928971693.pdfIn PDF document text
    • https://vnmmalta.com/userfiles/file/8631063987.pdfIn PDF document text
    • http://phuquytravel.com/nguyenvanlinh/files/31802789055.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=breakouts+around+mouthPDF 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_off0000d493.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD493 19660 bytes
SHA-256: 55bc56d8137a602d278153e6be07965140f327e202791c0d75ccc4a4d32074e1
font_01_sfnt_off00010761.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10761 10620 bytes
SHA-256: 11f4aab0c5a954ae3f81fe7f4a9e1e8257ff832d38cea91366dd42b256fa6fe6
font_02_sfnt_off00011f82.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F82 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1