Malicious PDF — malware analysis report

Static analysis result for SHA-256 a79716ea2fbec654…

MALICIOUS

PDF

79.1 KB Created: 2021-09-05 20:08:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 9536d051dcef88167eec29748709b8be SHA-1: 856e905b861d34ca9db3398510b0a5036f1de51b SHA-256: a79716ea2fbec6541ebd2629e0b05b9265dae35cea0e5df22820b50cc54fa95a
176 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URIs, many of which point to potentially compromised websites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware delivery. The presence of multiple external URIs and the 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic point towards an attempt to exploit search engine visibility or user trust to drive traffic to malicious destinations.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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://yeosingol.com/FileData/ckfinder/files/20210829_FF3A44C59795CC57.pdf In PDF document text
    • http://mateuszkucharski.pl/admin/file/jidezelazitolelibobebe.pdfIn PDF document text
    • http://www.infranetltd.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f99768d3b40---55882992241.pdfIn PDF document text
    • https://travelsafeway.com/userfiles/file/79471616790.pdfIn PDF document text
    • http://www.dr.schure.net/ckfinder/userfiles/files/jiwivuje.pdfIn PDF document text
    • http://3gr-group.com/ci/userfiles/files/32515033629.pdfIn PDF document text
    • https://alphaveneers.co.uk/wp-content/plugins/super-forms/uploads/php/files/996013dc4ca1053ada4df0b00c7a65f5/42992120508.pdfIn PDF document text
    • https://gresathouse.com/wp-content/plugins/super-forms/uploads/php/files/cc240a402ecbbbdfb11758f9f8870be7/80658671509.pdfIn PDF document text
    • http://metalzilembo.it/userfiles/files/7358485750.pdfIn PDF document text
    • https://www.saammohaseb.ir/wp-content/plugins/super-forms/uploads/php/files/2284e557b230ec2ee8714df2227b5fec/sefonopomosabasijupo.pdfIn PDF document text
    • http://mrybalko.ru/files/90917793927.pdfIn PDF document text
    • https://readxyz.com/wp-content/plugins/super-forms/uploads/php/files/3d649109185b6f9c4ea458f8f7d94a78/pifojawer.pdfIn PDF document text
    • https://vegas-shop.net/uploads/files/11828171798.pdfIn PDF document text
    • https://syntellect.ru/Repository/file/xixamuwusaweto.pdfIn PDF document text
    • http://elyriahigh1974.org/clients/0/05/052ab20d644b737728595af1a47b4450/File/4811926080.pdfIn PDF document text
    • http://for-rent-leuven.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606e1294417b2---lojizutufip.pdfIn PDF document text
    • http://mcutech.net/upload/2021/08/file/1628269123706031321.pdfIn PDF document text
    • https://faktxeber.com/resimler/files/rolivesunakeg.pdfIn PDF document text
    • https://tabularasa.lv/sites/tabularasa/uploads/documents/files/zesararemoze.pdfIn PDF document text
    • http://babamoleskine.com/files/file/furezaganamotito.pdfIn PDF document text
    • http://www.hkqi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ade0b32136f---dokugesa.pdfIn PDF document text
    • http://xn--80aaae7amexjfdlfdfg.xn--p1ai/files/file/41412083788.pdfIn PDF document text
    • http://antonioruizabogados.es/userfiles/file/93961478188.pdfIn PDF document text
    • http://140.121.161.111/ckfinder/userfiles/files/97649754991.pdfPDF link annotation
    • http://whatdwellswithin.com/file/rokazi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=display+two+excel+worksheets+side+by+sidePDF 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_off0000cfc7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCFC7 17540 bytes
SHA-256: 83d737d01ef9aacb2c3985d65817c71152853e6fdb5b01805d1f3c1778b92e07
font_01_sfnt_off0000fcd5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFCD5 11044 bytes
SHA-256: 98a8ad102c676c43255b9dbaa874032b3c21285c5d74a63bbbed75ccc43f452e
font_02_sfnt_off00011690.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11690 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1