Malicious PDF — malware analysis report

Static analysis result for SHA-256 66c8a01e71d20e7b…

MALICIOUS

PDF

75.0 KB Created: 2021-07-03 06:11:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 7d9b2ad8fe377267b19c11b21804e762 SHA-1: 2923c728ca61efaf414f698b1d56f78dc6585348 SHA-256: 66c8a01e71d20e7b2e1fd7179d26cc1c48f33f731845a532a360f5495c4db843
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to other PDF files hosted on compromised websites, indicating a link farm designed to distribute malware. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution. No scripts were extracted, but the structure points to a multi-stage attack where the initial PDF serves as a lure to download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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 https://assurancemauricie.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e8e0814421---wugadokelelalixowa.pdf In PDF document text
    • http://xn--80akij1ajew.xn--p1ai/wp-content/plugins/formcraft/file-upload/server/content/files/160bc9c5a27090---miginuv.pdfIn PDF document text
    • https://www.xcelsus.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609af5fa6c721---bejukaroxozedipetat.pdfIn PDF document text
    • https://nuevocoach.co.uk/wp-content/plugins/super-forms/uploads/php/files/afbfc3e533017c6ed22c191034ffc946/49318971449.pdfIn PDF document text
    • https://muratay.nl/userfiles/file/gelen.pdfIn PDF document text
    • http://ezibra.pl/upload//file/70018349487.pdfIn PDF document text
    • http://verdantnorwich.com/clients/3/30/306756bb587dffcd11ca74610d845a16/File/67280290401.pdfIn PDF document text
    • https://jdlpartnerss.com/userfiles/file/32846911067.pdfIn PDF document text
    • http://vitali-schulz-eiskunstlaufen.de/userfiles/files/lujefavagewowozetuz.pdfIn PDF document text
    • http://thaimassagemodel.com/ckfinder/userfiles/files/38250047686.pdfIn PDF document text
    • https://perleyparish.org/wp-content/plugins/super-forms/uploads/php/files/22c7fa348768d3b808941e62f372ef5c/46806259968.pdfIn PDF document text
    • https://ivanamihic.com//files/33284690841.pdfIn PDF document text
    • https://sgdivorcelawyers.com/wp-content/plugins/super-forms/uploads/php/files/3c5bf20d3ac7493a3c882805b068e69d/36459444021.pdfIn PDF document text
    • http://hoadon-dientu.net/images/files/21069767670.pdfIn PDF document text
    • http://itssilvertime.com/clients/2/24/24efe347a73a8ce028152bf895bc11a7/File/96466300691.pdfIn PDF document text
    • http://attlas.center/userfiles/file/taxolajijazem.pdfIn PDF document text
    • https://postelezmasivu-zlin.cz/ckfinder/userfiles/files/5347580295.pdfIn PDF document text
    • http://goldnumber.info/userfiles/file/nuzadilijugo.pdfIn PDF document text
    • http://israel-aliya.com/wp-content/plugins/super-forms/uploads/php/files/d2aaa1ee7b2809f37717ec6f8d0dfd44/filurusatalexekelaxu.pdfIn PDF document text
    • http://lamachine.nl/userfiles/file/korumogojulux.pdfIn PDF document text
    • https://www.hotel-palladium.gr/wp-content/plugins/super-forms/uploads/php/files/c1di1rmde4tejits4gmnl8lrmv/geniror.pdfIn PDF document text
    • http://zonweringnederland.com/ckfinder/userfiles/files/10475159531.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=x+by+10+100+and+1000PDF link annotation
    • http://e1pl2.nazwa.pl/busy/fotki/file/66265561967.pdfIn PDF document text
    • 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_off0000bc80.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBC80 23688 bytes
SHA-256: f26781114736795feb740272730b0c17c990a6b369be535ba0e54e38bf1a58df
font_01_sfnt_off0000f121.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF121 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010937.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10937 9920 bytes
SHA-256: 68bc94a3661d0a84e4466c17d407cc5fa03e6d87deb6a89f2c2e59454eaee669