Malicious PDF — malware analysis report

Static analysis result for SHA-256 08773dbcb2643e1a…

MALICIOUS

PDF

78.7 KB Created: 2021-09-24 22:48:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 7b7748b613e944e823c5754cbbcd88b7 SHA-1: 959a84a852efaddd8967d0904e16906d6267eab0 SHA-256: 08773dbcb2643e1a6c813cab756aa6471fa4037688e8d9c0c061581280bfddea
156 Risk Score

Malware Insights

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

The PDF contains a link farm directing to multiple URLs, several of which are hosted on compromised WordPress sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. No scripts were extracted, and the document body was unreadable binary data.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://arenda-v-novosibirske.ru/ckfinder/userfiles/files/43659510207.pdf
    • http://kidsjeodo.com/images/files/37763130351.pdf
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/0t8t24bia0ipn1ev3kj67pmvj4/lilores.pdf
    • http://mygotour.com/FileData/ckfinder/files/20210906_DCE7F45EFC5C3C47.pdf
    • https://www.bouldersudbury.org/wp-content/plugins/formcraft/file-upload/server/content/files/1614c6ef4bc76a---moliwewopusajunudiba.pdf
    • https://monarchwinemerchants.com/wp-content/plugins/super-forms/uploads/php/files/ba745774d98fd9e1676ffcee54830972/roxufufepilul.pdf
    • http://gwtcs.org/Content/uploads/files/83824465957.pdf
    • https://renetravel.ro/images/files/69557875820.pdf
    • https://mimpishiosatu.com/contents/files/38631480720.pdf
    • http://mid-europe-ex.com/images/blog/file/18574859672.pdf
    • https://discovercefalu.com/_data/images/file/daxan.pdf
    • https://www.spoton.pet/wp-content/plugins/super-forms/uploads/php/files/gbonc7dbtvi1qrit2i1hvbikc4/20297094686.pdf
    • http://expertsystemgroup.com/file_media/file_image/file/58729261715.pdf
    • http://adaviestransportltd.com/userfiles/file/dunitedomavodubekexixuz.pdf
    • http://ukwoodrecycling.com/userfiles/files/49774066519.pdf
    • https://piphoto.tw/uploads/files/202109040702524250.pdf
    • http://marthomaiticherukole.com/userfiles/file/44229869005.pdf
    • https://mumegram.com/userfiles/file/2980434898.pdf
    • http://hoanhaochemical.com/uploads/files/xujawaje.pdf
    • http://makesrealsense.com/ckfinder/userfiles/files/jomameso.pdf
    • http://agataklimowska.pl/userfiles/file/10091229575.pdf
    • http://milcontabil.com.br/wp-content/plugins/super-forms/uploads/php/files/fmevuodudkae54eek0k4v7m4b4/22746550755.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=market+leader+extra+intermediate+pdf
    • 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_off0000ca1b.bin
b34370ec2c863292eca99afcf25b251d42554fb846949b4ce96aedc9d6c72f0c
pdf-font-stream PDF embedded font (sfnt) at offset 0xCA1B 19592 bytes
font_01_sfnt_off0000fd27.bin
f593d357f8db8f329301c92b7bf816f7e4e7039d1df4e62b3ef36ddce1f0653a
pdf-font-stream PDF embedded font (sfnt) at offset 0xFD27 10560 bytes
font_02_sfnt_off00011528.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11528 16792 bytes