Malicious PDF — malware analysis report

Static analysis result for SHA-256 e51fefe761df9e69…

MALICIOUS

PDF

82.4 KB Created: 2021-09-17 21:29:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: bd9df86d292e55a29cc496ca22b32fae SHA-1: 25147fd06c0c094bab6d50bad22ab43647e0c5b7 SHA-256: e51fefe761df9e69fd6c9f81b504b6528da6096039da49444d267b5eff446ac6
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous links pointing to various domains, many of which are hosted on compromised WordPress sites or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution through these links. No scripts were extracted, and the document body was unreadable, but the link farm structure and heuristic firings are sufficient to assess the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 http://realcomfort.ru/content/upload/file/68471810700.pdf In PDF document text
    • https://emotionalgift.com/ckfinder/userfiles/files/dexiwutefarojol.pdfIn PDF document text
    • http://mitchelllawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/41763880595.pdfIn PDF document text
    • http://ladispensadicampagna.it/uploads/assets/file/gibazufix.pdfIn PDF document text
    • https://lostsoulsmemorialnj.org/wp-content/plugins/super-forms/uploads/php/files/aff8d3492ed8909ebd686ee6356fa5cf/6986352709.pdfIn PDF document text
    • http://cheumst.com/upload/fckeditor/file/59507011940.pdfIn PDF document text
    • http://erfolgsapp.de/wp-content/plugins/formcraft/file-upload/server/content/files/1612f5b99c6fb0---69474850882.pdfIn PDF document text
    • http://brezov-gaj.si/uporabnik/file/26125541814.pdfIn PDF document text
    • https://nuevocoach.co.uk/wp-content/plugins/super-forms/uploads/php/files/f23d69f24ee7bef3973293f616ca91bb/zemuwelasikaxido.pdfIn PDF document text
    • http://sanzmendia.com/userfiles/files/18606921904.pdfIn PDF document text
    • http://jubangh.com/Upload/FckUpload/20210914file///loninozafiketuwuj.pdfIn PDF document text
    • https://8foro.exceltur.org/exceltur_nuevo/ckfinder/userfiles/files/21656386014.pdfIn PDF document text
    • https://acp-luxusingatlanok.hu/ckfinder/userfiles/files/2517539857.pdfIn PDF document text
    • http://hasanmasat.com/ckfinder/userfiles/files/sajefavadusorusu.pdfIn PDF document text
    • http://abwcrainhwy.com/uploads/files/2683419838.pdfIn PDF document text
    • https://www.intermediastudios.com.mx/wp-content/plugins/super-forms/uploads/php/files/2e3ab06bfc4ac80be5f2943bc73ce76c/zitimagasuge.pdfIn PDF document text
    • http://tbvshungviet.com/upload/files/wifune.pdfIn PDF document text
    • https://alshaabcoop.com/userfiles/file/93535987031.pdfIn PDF document text
    • http://kayamedbursa.com/userfiles/file/97901200349.pdfIn PDF document text
    • http://tractortools.cz/ckfinder/userfiles/files/mujazetitutubetomodav.pdfIn PDF document text
    • http://fantacyhandicraft.com/userfiles/file/48632506417.pdfIn PDF document text
    • http://baruraprotidin.com/assets/ckfinder/core/connector/php/uploads/files/6907826242.pdfIn PDF document text
    • https://33mobility.net/uploads/files/98719616746.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=polarr+apk+downloadPDF link annotation
    • https://mediaget.com/userfiles/files/94900763047.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_off0000e01a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE01A 10076 bytes
SHA-256: 654726bf6353d86e6c584c94693c736e3f86d50acbd807d470f66e298be6b222
font_01_sfnt_off0000f6a0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6A0 17820 bytes
SHA-256: 9e49d5da9dacacb1fe9a7c7ec86f56f502cf3576a966aab023f306eef36d131c
font_02_sfnt_off00012406.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12406 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1