Malicious PDF — malware analysis report

Static analysis result for SHA-256 ff819fa0e5cfda4f…

MALICIOUS

PDF

73.0 KB Created: 2021-09-14 07:16:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: ebe711c7dc5bc793d02025f8c56a50a4 SHA-1: 7ed82f74397a579c09bedc39341f417b1f4a996e SHA-256: ff819fa0e5cfda4f7a8edfec38f38b788b0aec757385fc969ebe856aaf91f1ae
156 Risk Score

Malware Insights

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

The PDF contains multiple heuristics indicating it is a link farm hosted on potentially compromised websites, designed to redirect users to other malicious or unknown URLs. ClamAV and ML classifiers also flagged this PDF as malicious, specifically as a phishing trojan. The presence of numerous links to external sites, some hosted on compromised CMS uploads, strongly suggests an intent to distribute malware or conduct phishing operations.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://drmiamiconnect.com/wp-content/plugins/super-forms/uploads/php/files/d031e72cb69e0e55bddb37856241af38/28608501033.pdf In PDF document text
    • https://vetregistr.com/ckfinder/userfiles/files/lipawuxadam.pdfIn PDF document text
    • http://ahrestygz.com/userfiles/files/20210906_045557.pdfIn PDF document text
    • http://vtracauto.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139d0a58abc9---dewemewitizasovije.pdfIn PDF document text
    • https://solelane.com/ckfinder/userfiles/files/bopidaxizudafa.pdfIn PDF document text
    • http://slmj8.com/data/userfiles/files/58725673234.pdfIn PDF document text
    • http://kondicionery-elektrostal.ru/upload_picture/file/mibulire.pdfIn PDF document text
    • http://yushendesign.com/images_fck/file/1630973833.pdfIn PDF document text
    • http://rigosarchitects.gr/userfiles/file/96906766502.pdfIn PDF document text
    • http://studioturina.com/userfiles/files/90050605347.pdfIn PDF document text
    • https://www.sevgiliyevideo.net/wp-content/plugins/formcraft/file-upload/server/content/files/16136f84ab27ec---nijogeredirujovituwejakax.pdfIn PDF document text
    • https://godparents4tz.org/home/god/public_html/ckfinder/userfiles/files/89944528296.pdfIn PDF document text
    • http://westfallassociates.com/documents/file/51101036392.pdfIn PDF document text
    • https://univerosg.com/ckfinder/userfiles/files/dexukuke.pdfIn PDF document text
    • http://quincy.pl/ckfinder/userfiles/files/63383612292.pdfIn PDF document text
    • https://tourgardan.com/basefile/tourgardancom/files/43741113873.pdfIn PDF document text
    • https://omprintandpack.com/userfiles/file/zojetowezenovazisu.pdfIn PDF document text
    • http://www.protectakoteasia.com/ckfinder/userfiles/files/33077632883.pdfIn PDF document text
    • http://klimatyzacjaradom.pl/userfiles/file/44693793133.pdfIn PDF document text
    • https://elegune.net/files/galeria/files/zazibif.pdfIn PDF document text
    • http://triple-a.co.th/ckfinder/userfiles/files/14869057500.pdfIn PDF document text
    • http://makaifruits.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613018e8a3ee9---zerevijenixejusujuwi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=why+does+it+say+safe+mode+on+my+phonePDF 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_off0000bc24.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBC24 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d43b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD43B 10724 bytes
SHA-256: d489376afbbc503238120f48c3d10d16759b52f0fd03125adda83c4e19d9f540
font_02_sfnt_off0000ecba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECBA 16320 bytes
SHA-256: 597ea36a1db3f02ca3ad06fb1e0b73fbcd7828c6881cb1246fb9ad058afab487