Malicious PDF — malware analysis report

Static analysis result for SHA-256 4097f3450b1b0ae7…

MALICIOUS

PDF

71.5 KB Created: 2021-09-29 06:41:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 608f10f309f4496d3bb6a19e1c713623 SHA-1: 0c70e95ee68126c288d0aaaae814df0ec59e4269 SHA-256: 4097f3450b1b0ae7cfbf1623a9bda31b464f9be06148cfc7972951ebc1625c88
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ML classifiers and ClamAV, specifically as a phishing trojan. Static analysis revealed it functions as a link farm, containing numerous URLs pointing to various domains, some of which are hosted on compromised WordPress sites or appear to be disposable. The presence of these links suggests an intent to lure users to malicious sites for phishing or further payload delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://around-sicily.net/userfiles/file/nurijamabuwukis.pdf
    • http://www.eflox.net/wp-content/plugins/formcraft/file-upload/server/content/files/1613488dc0722e---51381027963.pdf
    • https://bgg.pirkitpadangas.lt/ckfinder/userfiles/files/63635999136.pdf
    • http://zelene-centrum.cz/webpagebuilder/ckfinder/userfiles/files/63076859110.pdf
    • http://global-gypsum.com/wp-content/plugins/formcraft/file-upload/server/content/files/161438e136affc---92065778961.pdf
    • http://desushibar.com/userfiles/file/basaje.pdf
    • http://slowjamsundays.com/wp-content/plugins/formcraft/file-upload/server/content/files/161340a0097a35---67214956165.pdf
    • http://traiteur-ribot.fr/userfiles/file/tutekuveposugekigixubo.pdf
    • http://thomas-zigon.de/images/file/20510410609.pdf
    • https://nutricount.cz/UserFiles/File/xepukitepoganog.pdf
    • https://penzionradvanice.cz/res/file/nibowugitukexe.pdf
    • http://rhondachem.com/d/files/77308038925.pdf
    • https://foodexgida.com/uploads/files/rolipazipasarozezemofev.pdf
    • https://sandp-engineering.com/ckfinder/userfiles/files/zagupakigelukilevabowa.pdf
    • http://odesignlab.ru/admin/ckfinder/userfiles/files/rasufirosibol.pdf
    • http://vpecargo.com/userfiles/file/dolupukiwufanut.pdf
    • https://hoakhanh.vn/uploads/image/files/pijubelavunedaboxebo.pdf
    • https://livresdarts.com/ckfinder/userfiles/files/71266041554.pdf
    • http://ecosdaliberdade.com/ckfinder/userfiles/files/fegixefa.pdf
    • https://weekendtripskolkata.com/userfiles/file/golebikapimubemofefoduf.pdf
    • http://oticonshop.com/ckfinder/userfiles/files/19380551850.pdf
    • http://restravel.ru/ckfinder/userfiles/files/73652372297.pdf
    • http://kpotplace.com/uploads/files/49593242309.pdf
    • http://pepinieres-soupe.com/userfiles/file/noxulemipojikiju.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=bike+unchained+2+apk
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b5ca.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB5CA 16792 bytes
font_01_sfnt_off0000cde1.bin
ca3b16aabc281e1da3d638eefead8a07a72b85829bdb11f579af69c4ed52c697
pdf-font-stream PDF embedded font (sfnt) at offset 0xCDE1 10444 bytes
font_02_sfnt_off0000e57f.bin
fa42e5ce6ed61c70406a6413fd4692e18e0d7e2e875eeb278a3209f491ba8f7a
pdf-font-stream PDF embedded font (sfnt) at offset 0xE57F 16720 bytes