Malicious PDF — malware analysis report

Static analysis result for SHA-256 844a525889f75f7e…

MALICIOUS

PDF

107.9 KB Created: 2021-06-28 13:55:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: e4dd10615271484dcb0025c89ab438e6 SHA-1: 208d39fdd75fabb42a42427fa913d7c5db0f384c SHA-256: 844a525889f75f7e9197238ad3dac79881f370fc24a8485b3b7f840887f99f03
156 Risk Score

Malware Insights

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

The PDF contains a link farm with numerous URLs pointing to compromised WordPress sites, indicating a phishing or malware distribution attempt. ClamAV detection and ML classification strongly suggest malicious intent. The document body is unreadable, but the heuristic firings and URLs confirm the nature of the attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9913

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://formapolis.it/wp-content/plugins/super-forms/uploads/php/files/83f1b16a98912e29c52c9fad744ad0ba/gumisogagoxuxefob.pdf In PDF document text
    • https://www.hotel-palladium.gr/wp-content/plugins/super-forms/uploads/php/files/qi1mddkvn00on4ggitkn875l3l/lirodisisobote.pdfIn PDF document text
    • http://metzpaintings.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073d4bc2e4a8---lenuxizijozezuzuka.pdfIn PDF document text
    • http://henri-ruch.ch/doc_pub/file/63054904244.pdfIn PDF document text
    • http://kimyasaldubeller.com/upload/ckfinder/files/20423096228.pdfIn PDF document text
    • https://popa.com.br/wp-content/plugins/super-forms/uploads/php/files/a5571b1d9b3b566ca7a5f2ee8ab26d1a/sodatududisikojupajipe.pdfIn PDF document text
    • http://kystop.com/wp-content/plugins/super-forms/uploads/php/files/rfu5l3f83miv59vth5347ibhl4/30213720799.pdfIn PDF document text
    • http://www.rebranded.tv/wp-content/plugins/formcraft/file-upload/server/content/files/160bcbd24dcd5a---12022417412.pdfIn PDF document text
    • https://luxmarketing.agency/wp-content/plugins/super-forms/uploads/php/files/mdpd3fvbhnt6df30dcf0fh85vu/vuxukireniwopuzixugelud.pdfIn PDF document text
    • http://www.suffaheducation.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bcc0eb3b1fa---96674213912.pdfIn PDF document text
    • http://gianphoiduyloimodel.com/Images_upload/files/zogimezopezedovigobojemu.pdfIn PDF document text
    • https://amartzon.store/wp-content/plugins/super-forms/uploads/php/files/521855a337dc28824642b81fa72df539/20571131347.pdfIn PDF document text
    • https://robinio.de/wp-content/plugins/super-forms/uploads/php/files/dlajpb26eme74kalh5bcb4fc5t/wamig.pdfIn PDF document text
    • https://www.horisunmauritius.com/wp-content/plugins/super-forms/uploads/php/files/d1dc52c3e0bdd5715bcc716ba98b5126/kifegamilezatodevoli.pdfIn PDF document text
    • http://carsongrad75.com/clients/3/35/35717660c32d3dd9b0ffde8f33a19d23/File/41939183163.pdfIn PDF document text
    • http://sciencevier.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608ba285d50de---finexoduvuwafuzemadusi.pdfIn PDF document text
    • http://royalwedding.jp/images/blog//file/88601617812.pdfIn PDF document text
    • https://yastudio.net/wp-content/plugins/super-forms/uploads/php/files/dce0f4d4baf070c8e6958e39e50f921b/torilorexo.pdfIn PDF document text
    • https://jdbailbonds.com/wp-content/plugins/super-forms/uploads/php/files/cc7ea772d79dc3d7c9a3b00d1972e6e3/gafejuwoziloroka.pdfIn PDF document text
    • https://purebodycare.courses/wp-content/plugins/super-forms/uploads/php/files/1g5t1hsajs7qmt0k126i1hm2dt/texawulunukokogu.pdfIn PDF document text
    • http://aftckwt.com/uploads/file/rezaxoridulejatojujal.pdfIn PDF document text
    • https://pluckywize.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072a0f5c9c9d---79355174536.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=tell+me+the+story+of+cain+and+abelPDF 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_003_off0001372c.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x1372C 18476 bytes
SHA-256: a1d596c8b47d6302bb290ba259e137e03e39ae9dd4b8d38b46b1f4fd77294ef0
font_00_sfnt_off00011df2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DF2 10956 bytes
SHA-256: e1ecc7f0289650893043b1f5d0ac2f24562bbe40fc10a4edf24fdf52046732a8
font_02_sfnt_off00015512.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15512 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_03_sfnt_off00016d24.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16D24 20952 bytes
SHA-256: db22c90c1ba655334762333fbc9fb42e13daadfd9647d56cbb4e949b20bf0f08