Malicious PDF — malware analysis report

Static analysis result for SHA-256 781851f4b3002203…

MALICIOUS

PDF

92.1 KB Created: 2021-09-01 06:00:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 446401ef61284c261d27aea70b7b6a9f SHA-1: 7ebe25fa353ef12d9d8b8e51d6be301e9d27d3ee SHA-256: 781851f4b3002203f31029c539f3087ca079642e6b33946dbe30b972e72f0552
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The PDF file contains numerous embedded URLs, many of which point to potentially compromised websites or directly to IP addresses. Heuristics indicate a link farm strategy, with some links hosted on compromised WordPress installations. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. No scripts were extracted, but the embedded links are the primary attack vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Clickable URI points to raw IP address medium PDF_URI_IP_LITERAL
    PDF contains a clickable HTTP(S) action whose host is a literal IPv4 address. Legitimate documents normally link to named domains; raw-IP destinations are common in disposable phishing and malware-delivery infrastructure.
  • 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://104.156.58.56/~web2inbox/wp-content/plugins/formcraft/file-upload/server/content/files/1607a6d4632326---97234848117.pdf PDF link annotation
    • http://cameronhaddock.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085c41da9c01---zuwutomupibiv.pdfIn PDF document text
    • https://aptitudeclass.com/ckfinder/userfiles/files/88420438564.pdfIn PDF document text
    • https://www.helmmsp.ca/wp-content/plugins/super-forms/uploads/php/files/44045ec0e86e000f7b971fec788273d9/16638301800.pdfIn PDF document text
    • https://www.taxiserviceh24.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c0c0d56bc5---vobawaxupolenutosexo.pdfIn PDF document text
    • http://feach.ie/images/uploads/file/bopexi.pdfIn PDF document text
    • http://akcjonariusz.com/UserFiles/file/32532738842.pdfIn PDF document text
    • http://www.korayozelguvenlik.com/wp-content/plugins/formcraft/file-upload/server/content/files/16091aa3758d27---zudivatem.pdfIn PDF document text
    • http://irvinenott.co.uk/ckfinder/userfiles/files/gazekonizimi.pdfIn PDF document text
    • https://westcoastmovers.ca/wp-content/plugins/super-forms/uploads/php/files/coidbg58jbsiovb3cu9r8n3k7l/51685920988.pdfIn PDF document text
    • https://e-ceramika.pl/userfiles/file/defejobupilojane.pdfIn PDF document text
    • http://musiclivemarsala.com/userfiles/files/zesivelikilinuk.pdfIn PDF document text
    • https://voyagerf.ru/wp-content/plugins/super-forms/uploads/php/files/8256918cf84fe80fe6da2933dbea9839/pepamixarubiwuxufebabi.pdfIn PDF document text
    • https://loskutova.site/wp-content/plugins/super-forms/uploads/php/files/4715e7605b7df80e14c2ccf6c7fa1d70/povobaw.pdfIn PDF document text
    • http://worshipedia.net/sites/default/files/file/ninajuvikozalevonir.pdfIn PDF document text
    • http://xn--b1akwe.xn--p1ai/userfiles/file/21625669282.pdfIn PDF document text
    • http://ck-tct.ru/userfiles/file/34731190454.pdfIn PDF document text
    • https://carpanea.it/wp-content/plugins/super-forms/uploads/php/files/30ae41a3bd11eabcf98bf13fb2e436b0/10912626633.pdfIn PDF document text
    • http://life-worldwide.org/assets/uploads/files/5047916202.pdfIn PDF document text
    • http://studiogiovannone.com/userfiles/files/puduxiril.pdfIn PDF document text
    • https://nocnepal.org.np/ckfinder/userfiles/files/63005452284.pdfIn PDF document text
    • https://deewo.de/wp-content/plugins/formcraft/file-upload/server/content/files/160ad207b98a64---6649107744.pdfIn PDF document text
    • https://www.edmcenter.xyz/ckfinder/userfiles/files/95185147413.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=compliment+words+that+start+with+pPDF 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_off000103ef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103EF 17628 bytes
SHA-256: 3c6fddf1924e4c35ba5fb5c767b53c375468c44fd99b146d53503ff064ee35fe
font_01_sfnt_off00013175.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13175 10772 bytes
SHA-256: f492ac52b3bb2972429a81669c2312d3a4eded2e5ac5a90f6f796051905ec934
font_02_sfnt_off00014a14.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14A14 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1