Malicious PDF — malware analysis report

Static analysis result for SHA-256 c8ce9207f2397f7c…

MALICIOUS

PDF

80.8 KB Created: 2021-09-20 10:11:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 272393eb5a00e1cc1c1f22241d2fd482 SHA-1: dfa286df2236f5970de497f0357a20c9fb9913d9 SHA-256: c8ce9207f2397f7c15cd22ecd68b4906454b11b50dbd6075069c2ba7f05a79af
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs pointing to a link farm, indicating a likely phishing or malware distribution scheme. The 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic further supports this, noting a high number of distinct hosts and links. No scripts were extracted, but the overall structure suggests an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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://leise.ru/admin/ckfinder/userfiles/files/sexalumajuse.pdf In PDF document text
    • https://bela.geekers.tw/upload/file_folder/file/81925236791.pdfIn PDF document text
    • http://ledins.lv/cms/file/demixexizujekug.pdfIn PDF document text
    • http://riasztoszolnok.hu/admin/fck_upload/file/51638124588.pdfIn PDF document text
    • https://arhometutor.com/userfiles/file/35951490315.pdfIn PDF document text
    • http://greenvisioninternational.gm/userfiles/file/83990565173.pdfIn PDF document text
    • http://insfilings.com/skyzone_classic/upload/files/buligosulizel.pdfIn PDF document text
    • http://silarperu.com/UserFiles/file/tasumimuzitafigedefobu.pdfIn PDF document text
    • https://kingcarmotorista.net/uploads/files/detanepibitivupala.pdfIn PDF document text
    • http://anabakorea.jp/userfiles/file/wusif.pdfIn PDF document text
    • http://jlsxjy.com/right/UploadFile/file///2021092005335373499.pdfIn PDF document text
    • https://brawlcall.jordanadams.com/ckfinder/userfiles/files/62249426753.pdfIn PDF document text
    • http://viswinkelindex.nl/images/uploads/rosasuzaxalumulove.pdfIn PDF document text
    • http://octapus.vn/images/uploads/files/10626549795.pdfIn PDF document text
    • http://vakantie-noordlimburg.nl/ckfinder/userfiles/files/6912738944.pdfIn PDF document text
    • http://shopcode.ru/uploads/file/wejolufivigodilumu.pdfIn PDF document text
    • http://lerucherdesanges.fr/userfiles/file/60924716001.pdfIn PDF document text
    • https://sieuthimayphat.com/ckfinder/userfiles/files/ruzomubuvekigeri.pdfIn PDF document text
    • https://trainova.com/userfiles/file/gutokige.pdfIn PDF document text
    • http://kidneytracker.com/ckfinder/userfiles/files/zuvijugonirozuk.pdfIn PDF document text
    • http://pepinieres-soupe.com/userfiles/file/fevudifuzifijoxobusiv.pdfIn PDF document text
    • http://speckletrack.com/update/editor/file/kebugaf.pdfIn PDF document text
    • http://mama-care.com/UserFiles/file/pixodipajajasofepomejit.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1612f6a1285e33---pojovavudekuwedunegolib.pdfIn PDF document text
    • http://franceplus.fr/userfiles/file/busedobusepe.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=elementary+english+test+pdfPDF 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_off0000d1dc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD1DC 19492 bytes
SHA-256: c463a1339973690392bd76f24d05123cb710c98c2c1ccac5838293f9f477beee
font_01_sfnt_off000104f9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104F9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011d10.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D10 10924 bytes
SHA-256: 426a2b81ffd155251a9a9e636862219f21267220c5447912219da62b12d8f585