Malicious PDF — malware analysis report

Static analysis result for SHA-256 ef7c119b15ea1521…

MALICIOUS

PDF

80.6 KB Created: 2021-09-17 21:35:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 386e73c0bf322dd8238b343387da4ca9 SHA-1: 5cd20f1e668f8b3e7de72af3623c236d6db0d35e SHA-256: ef7c119b15ea15215d96f8a915816065f9ff266e90229472e72a12cf297c0924
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document contains a high number of embedded links pointing to various domains, many of which are hosted on disposable or suspicious infrastructure. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The presence of numerous external URIs and the link farm heuristic suggest a coordinated effort to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://allytemp.ru/uplcv?utm_term=mobile+uncle+tools+apk PDF link annotation
    • https://frutalmente.pt/site/upload/file/53579135894.pdfIn PDF document text
    • http://www.telsercom.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612ed95866e18---kejifewimurijexutuxu.pdfIn PDF document text
    • http://bergfin.se/wp-content/plugins/formcraft/file-upload/server/content/files/16131c4af376ea---tevejikejemasazeromevid.pdfIn PDF document text
    • http://dh-life.com/ckfinder/userfiles/files/53826943512.pdfIn PDF document text
    • http://rutka.pl/media/upload/files/8fa719f36d733fba122355e1f6aaa7b8.pdfIn PDF document text
    • http://gzmzwl.com/Uploadfiles/files/45989036196.pdfIn PDF document text
    • http://www.saito-ken.jp/userdata/file/luman.pdfIn PDF document text
    • http://mu-rrrc.com/userfiles/file/vinuzitizo.pdfIn PDF document text
    • http://master-br.ru/img/file/45221756293.pdfIn PDF document text
    • http://baobianhkhang.com/upload/files/32562426488.pdfIn PDF document text
    • http://ecme.site/2015/vat/upload/files/rapapekudatajapekuvigapat.pdfIn PDF document text
    • https://bosingels.nl/ckfinder/userfiles/files/79602355996.pdfIn PDF document text
    • http://elskup.pl/images/assets/file/32888910821.pdfIn PDF document text
    • http://vizit-k.net/uploads/editor/files/72276966088.pdfIn PDF document text
    • http://geose.ru/userfiles/file/satujadidegudikitipetapa.pdfIn PDF document text
    • https://www.kiemtoandongnghi.com/public/plugins/ckfinder/userfiles/files/9811986847.pdfIn PDF document text
    • http://modern-pro.ru/files/file/44574785706.pdfIn PDF document text
    • https://www.emcp-pmce.ca/_includes/ckfinder/userfiles/files/pezagoxe.pdfIn PDF document text
    • https://synodradomski.pl/userfiles/file/baxijojafikujulekek.pdfIn PDF document text
    • http://goopenapp.com/uploads/files/fibenunifawesuku.pdfIn PDF document text
    • http://pololanna.com/user_img/files/bigofovesenoletetobuno.pdfIn PDF document text
    • http://donghotam.com/luutru/files/76694692269.pdfIn PDF document text
    • https://ctcitsupport.com/media/files/23570909952.pdfIn PDF document text
    • http://volareinmongolfiera.it/userfiles/files/18561128341.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_off0000d731.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD731 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ef43.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF43 17764 bytes
SHA-256: 5a753a8b5342d653adfdfd53f92c6339ab4bf3c9cd7ef05742d8350204b58fcb
font_02_sfnt_off00011d36.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D36 10592 bytes
SHA-256: c883f576ed11fe6910d98e00270ee70a34f5604ca6bf7743ea5726d8cb38e0aa