Malicious PDF — malware analysis report

Static analysis result for SHA-256 cbb7d08246a79ab3…

MALICIOUS

PDF

71.5 KB Created: 2021-09-19 06:52:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d60c9b701c861e48dfe3cd44de81430f SHA-1: 57ffb4220fe17b1b329652944224827e01b87ddc SHA-256: cbb7d08246a79ab3d1dbd341af61a63affcd5dd7b6e917789ff344f6b65b024c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many of which are hosted on compromised WordPress sites or disposable domains, indicating a link farm or phishing lure. The ClamAV detection and ML classifier strongly suggest malicious intent. While no scripts were explicitly extracted, the PDF structure and embedded URLs point towards an attempt to redirect users to malicious content, likely for phishing or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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 https://cructi.ru/uplcv?utm_term=boxing+stream+websites
    • http://oipipleszno.pl/userfiles/file/71799709920.pdf
    • http://b40555.handyfriendship.com/upload/files/57578955150.pdf
    • https://dcicz.org/userfiles/file/salekemekotibevevino.pdf
    • http://ammk.sk/userfiles/file/47318397957.pdf
    • http://bsl-trans.ru/admin/ckfinder/userfiles/files/kinegewonesulibisomemelo.pdf
    • http://hauptlawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/22223783646.pdf
    • https://accesoriosalmayor.com/images/userfiles/file/6095458856.pdf
    • https://pabausa.org/wp-content/plugins/formcraft/file-upload/server/content/files/16139b2a734c7a---kerazuwugejo.pdf
    • http://lnaixi.com/userfiles/file/20210908202553_219301046.pdf
    • http://calisnt.com/uploads/files/tegepipepazov.pdf
    • http://skipjackpoke.com/ckfinder/userfiles/files/69874768613.pdf
    • https://beautyyaurient.com/editor_upload/file/gasodamodanisukaxota.pdf
    • https://n-vv.dk/userfiles/file/darupek.pdf
    • https://ateneoarbonaida.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140f8bd8b3e5---86063142846.pdf
    • https://pmcp-avac.com/files/upload-ckfinder/files/90621753430.pdf
    • https://yarsan.ru/wp-content/plugins/super-forms/uploads/php/files/d751e2b427d0332ad8da737937fdc007/93675745127.pdf
    • http://dar-tom.pl/userfiles/file/4401898782.pdf
    • https://fsreloading.com/userfiles/files/renoxi.pdf
    • http://nuovartea.eu/userfiles/files/raketunafarufivujipid.pdf
    • http://spartapr.com/images/upload/file/70247995105.pdf
    • https://dynasty888.com/image/files/20210904_182416.pdf
    • http://randygordonlawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/53367877729.pdf
    • http://hferrynetworks.com/FileData/ckfinder/files/20210909_C344EB0FBD26E3DA.pdf
    • https://tjp2-hotlink-j3t.com/contents/files/52344597276.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_off0000b3b0.bin
4d33b4c11512550c72746920f207730e1816f5b55cae681daeb15abc559f9b92
pdf-font-stream PDF embedded font (sfnt) at offset 0xB3B0 17192 bytes
font_01_sfnt_off0000dfe8.bin
855d9df5edae74645a6f5a24da8367a3d3e19d35b0caea896a2113272295e3d3
pdf-font-stream PDF embedded font (sfnt) at offset 0xDFE8 10788 bytes
font_02_sfnt_off0000f8ea.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF8EA 16792 bytes