Malicious PDF — malware analysis report

Static analysis result for SHA-256 23a2a8bfceccfd2e…

MALICIOUS

PDF

79.6 KB Created: 2021-09-13 06:48:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: c5c66376dab32493c78fbf505dfc1ec5 SHA-1: a722830569d7f2ae3b203da2e25066dc80ca5438 SHA-256: 23a2a8bfceccfd2e6f94ee33680bcb83b0953b4ed65c30aec33ba88cc66004fa
156 Risk Score

Malware Insights

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

The sample is identified as malicious by ML classifiers and ClamAV, specifically as a phishing trojan. It functions as a link farm, with numerous URLs pointing to potentially compromised or disposable hosting, aiming to lure users to malicious content. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicates a deliberate attempt to obscure the true destination through redirectors.

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://zopos.zohukum.com/ckfinder/userfiles/files/boxutagadisowupobapesif.pdf In PDF document text
    • http://newgatedesign.com/Images_upload/files/xiretavigezeloro.pdfIn PDF document text
    • http://master-vin.ru/files/file/82685649081.pdfIn PDF document text
    • http://szolnokepul.hu/userfiles/file/zilaparojorusaporu.pdfIn PDF document text
    • http://sakesushilakehavasu.com/uploads/files/tuvomefewibujafivil.pdfIn PDF document text
    • http://pn-tech.net/userData/board/file/30244221137.pdfIn PDF document text
    • https://lecachet.fr/docs/files/vigawakoforefutini.pdfIn PDF document text
    • https://rosenstein.lu/userfiles/files/mufubagobigozigetozaf.pdfIn PDF document text
    • https://footballsod.com/images/ck-uploads/files/pokebe.pdfIn PDF document text
    • https://binarbaidtrading.com/public_html/userfiles/file/28315057379.pdfIn PDF document text
    • https://avigailpekelman.com/sites/default/files/file/35680757215.pdfIn PDF document text
    • http://alda.pl/ckfinder/userfiles/files/96071952425.pdfIn PDF document text
    • http://boonfagrandhome.com/user_img/files/nutotimobizeruvewebitop.pdfIn PDF document text
    • http://www.yourhealthyourchoice.org/wp-content/plugins/formcraft/file-upload/server/content/files/1613ebbcecb4b0---zafelomuvugodiwapap.pdfIn PDF document text
    • https://wyslijpaczki.pl/app/webroot/files/userfiles/file/fegizobexezenezew.pdfIn PDF document text
    • http://noithatphathuy.com/Images_upload/files/95223042954.pdfIn PDF document text
    • http://leap-egypt.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b8b37a5b50---4218367378.pdfIn PDF document text
    • http://meubelenindex.nl/images/uploads/92119658394.pdfIn PDF document text
    • http://miet-boot.ch/images/uploadedimages/file/jovugavejepewerozot.pdfIn PDF document text
    • https://amigo-shop.105h.net/upload/files/nokejivediruw.pdfIn PDF document text
    • https://sadex.pl/fck/file/dotaxekuzoma.pdfIn PDF document text
    • https://robertmatzuzi-massagetherapist.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1613dda15a9643---30300901674.pdfIn PDF document text
    • http://an-ocn.ru/ckfinder/userfiles/files/legopolijitoruginalexasi.pdfIn PDF document text
    • https://ajwatravel.com/wheelmarine/userfiles/file/luvixobu.pdfIn PDF document text
    • https://photographerin.agency/wp-content/plugins/super-forms/uploads/php/files/mcu7s9r28vrprtmj5qi6t74af1/kozezuja.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=watch+double+shot+at+love+season+2+online+freePDF 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_off0000d0fa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD0FA 10992 bytes
SHA-256: 4eb383b548a52d749cb25477f08a9085e858fec42d224050169913a8fe00a926
font_01_sfnt_off0000ea8e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA8E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000102a0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102A0 17604 bytes
SHA-256: f78eedb9753cd0d372f7680a7fd56ca6dacaf8a5e076bca248beb6b37f57da93