Malicious PDF — malware analysis report

Static analysis result for SHA-256 349cc473f33e1000…

MALICIOUS

PDF

79.8 KB Created: 2021-09-17 17:09:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: b756b10241da0d0c674018c3250689bd SHA-1: 91829dc82b1f9372d4274b9f85b00b926c28f165 SHA-256: 349cc473f33e1000407c10eb705a6ee916a12de2264a910aa3935ecdb7b1e74d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains a link farm hosted on multiple compromised websites, including a WordPress site. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to trick users into downloading further malware. The document body is heavily obfuscated and unreadable, providing no direct clues to its purpose beyond the embedded URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://hz-kontejnery.cz/ckfinder/userfiles/files/20780603180.pdf In PDF document text
    • http://chinalanpa.com/images/upload/File/20542914177.pdfIn PDF document text
    • https://webhostmurah.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613bbb7d76d00---36745258833.pdfIn PDF document text
    • https://www.jnvhardoi.org/ckfinder/userfiles/files/82520658471.pdfIn PDF document text
    • https://dewalt-naradi.cz/media/upload/editor/file/jasozujojunoxapi.pdfIn PDF document text
    • https://juniorclublivorno.com/sitonews/images_upload/files/53667368339.pdfIn PDF document text
    • http://smolensk-bakaleya.ru/userfiles/file/72660489034.pdfIn PDF document text
    • https://jss-moms.si/upload/File/7072727033.pdfIn PDF document text
    • http://chi-kara.net/Upload/files/josukidedanutalalojazu.pdfIn PDF document text
    • http://www.nationaalgolfcongres.nl/wp-content/plugins/formcraft/file-upload/server/content/files/161383f6666e1f---87906778860.pdfIn PDF document text
    • http://p-jtech.com/userData/board/file/3748495071.pdfIn PDF document text
    • https://nailseasupportgroup.com/wp-content/plugins/super-forms/uploads/php/files/bb5a8836c6e785ea83bcd04a7ad98e6c/57893499553.pdfIn PDF document text
    • http://air-con.ru/upload/files/3632063047.pdfIn PDF document text
    • https://hbphoto.ca/resimler/files/94411579090.pdfIn PDF document text
    • http://ceramicaartisticamarsalese.it/userfiles/files/zojefewovebibiz.pdfIn PDF document text
    • https://masukpt1.com/contents/files/sarosipozurojari.pdfIn PDF document text
    • https://preciseenergygroup.com/media/71627754227.pdfIn PDF document text
    • https://semot.com/Store/userfiles/file/48822118060.pdfIn PDF document text
    • https://coevent.ru/upload/files/nadimefitulenevogegigu.pdfIn PDF document text
    • http://relaxzenter.com/uploads/files/21478620719.pdfIn PDF document text
    • http://yishiweb.com/upfiles/files/20210917_112502.pdfIn PDF document text
    • http://gursakaryahukuk.com/images/file/15613737732.pdfIn PDF document text
    • http://udokutscher.de/gfx/userfiles/files/dujasubadajaxonetekef.pdfIn PDF document text
    • http://www.videobezopasnost.ru/ckfinder/userfiles/files/57748476650.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=apk+du+screen+recorderPDF 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_off0000d660.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD660 10280 bytes
SHA-256: 2bfb91a1b461fe131218c9afcf8b5e87bfe609ffc78a0abaa0d6827170ef26ab
font_01_sfnt_off0000eda1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDA1 17000 bytes
SHA-256: 03a6dadf8286fd1fb6fd2a8b334d27907e4853e6e250dfbabaff5d5d658fe4e0
font_02_sfnt_off00011996.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11996 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1