Malicious PDF — malware analysis report

Static analysis result for SHA-256 8c73f0618fd57aad…

MALICIOUS

PDF

83.6 KB Created: 2021-06-30 10:49:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 07644153aec640095186e7b53ef3ddb0 SHA-1: aaa643abf3cdc22a5791c576e59467b93316a938 SHA-256: 8c73f0618fd57aad11fff208bd74b825eb3d0a23c185f28826ed813cad7fd744
156 Risk Score

Malware Insights

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

The PDF contains numerous external links, many pointing to compromised WordPress sites, suggesting a link farm for SEO manipulation or to host malicious content. ClamAV detection and ML classification strongly indicate malicious intent. The presence of embedded URLs and the nature of the heuristics point towards a phishing or spam campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

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://cructi.ru/uplcv?utm_term=how+to+change+the+order+of+pages+in+pdf
    • http://www.hotel-margherita.com/wp-content/plugins/formcraft/file-upload/server/content/files/160947ca816a99---gejuloxetesejupekejusasit.pdf
    • https://www.themeshcowork.com/wp-content/plugins/super-forms/uploads/php/files/453173c8fd7813cab12be7bdb5d3b55a/nosedezakesorezoratibazu.pdf
    • https://foodvellythailand.com/upload/files/fowasa.pdf
    • https://btegypt.comfile/numozokunotaribefaxu.pdf
    • https://aftaplan.com/works/peepsparty/html/upload_files/file/rasinosapadezatewedoxav.pdf
    • http://www.miamiairportlimo.net/wp-content/plugins/formcraft/file-upload/server/content/files/160b45fe005146---gojipajomiliveziwumowod.pdf
    • http://www.davidwoodpersonnel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a3637669ffe---vodugefivobozoremubebosa.pdf
    • http://profisystem.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160bbd8c22a80c---dujatafugufidotoguzowe.pdf
    • http://icltindia.in/userfiles/file/91268691838.pdf
    • http://bagandpack.ru/wp-content/plugins/super-forms/uploads/php/files/0f869291b4e47acc3a0080cb8812f5e4/dujejimazomapur.pdf
    • https://ceilford.org/wp-content/plugins/super-forms/uploads/php/files/ced457cb2b2a89b08883b31f4786f8ca/74532427076.pdf
    • https://ipcare.nl/wp-content/plugins/super-forms/uploads/php/files/a5bq0tgvfkon1n9d31dllvq1u9/1415034033.pdf
    • http://reclaimsplus.com/wp-content/plugins/super-forms/uploads/php/files/495f5057559af7b57b74f4cba1cbf009/3311647125.pdf
    • https://www.hauptsache.cc/wp-content/plugins/formcraft/file-upload/server/content/files/160c52ac221995---84756717600.pdf
    • https://www.pfgpartners.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160a0698f32819---48225064723.pdf
    • http://indiebookoftheday.com/wp-content/plugins/formcraft/file-upload/server/content/files/160838098805b2---54383793035.pdf
    • https://www.scilights.com/wp-content/plugins/super-forms/uploads/php/files/070179250f5a1fa6ce5e90d71d8e8b70/rudurara.pdf
    • http://www.immiflex.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c725135587---63423284498.pdf
    • http://modnyi-buket.ru/uploads/files/zaxixokexubuxipebapuka.pdf
    • https://www.hdontheroadnapoli.it/wp-content/plugins/formcraft/file-upload/server/content/files/1606fb579d292d---16173589516.pdf
    • https://ilc.ua/wp-content/plugins/super-forms/uploads/php/files/dut48uhui007mknhd6nr2g3ot2/rubomoburexefotamofuvare.pdf
    • http://usarsenal.it/userfiles/files/80788351804.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e398.bin
22d7d77baf23c24fb9cb7772ce5da63464905e8c8f4f6c6b65c898490e31dc1e
pdf-font-stream PDF embedded font (sfnt) at offset 0xE398 16980 bytes
font_01_sfnt_off00010fc3.bin
5efc080906e4c5bc5a8891f8bfe55743b4715b5bc576a109c986379ebfa74520
pdf-font-stream PDF embedded font (sfnt) at offset 0x10FC3 10932 bytes
font_02_sfnt_off000128e1.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x128E1 16792 bytes