Malicious PDF — malware analysis report

Static analysis result for SHA-256 9187a33b137b2e38…

MALICIOUS

PDF

81.1 KB Created: 2021-09-05 16:17:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 7aa54509c7220c3d9b57ce17ee166459 SHA-1: e1911ce7e482bedc4a3f1ca932b7e7c88dd40f71 SHA-256: 9187a33b137b2e3825cf387cd1e5a9f4ba49c3fec07b1d9779370933f6ed601f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The document contains numerous links to external websites, many hosted on compromised CMS platforms or disposable domains, suggesting a link farm designed to redirect users to malicious content. The presence of PDF_URI and PDF_SEO_DISPOSABLE_LINK_FARM heuristics further supports this, indicating the document's primary purpose is to distribute links. Although no scripts were explicitly extracted, the nature of the links and the overall structure point towards a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9833

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://pixomot.ru/uplcv?utm_term=income+tax+depreciation+rate+pdf
    • https://bayardplaza.co.uk/wp-content/plugins/super-forms/uploads/php/files/tvbiurbr6tj0tbqln8u3aq0ak6/nukosisevo.pdf
    • http://oneself.pro/wp-content/plugins/formcraft/file-upload/server/content/files/1607e1a5c9d133---gijogowu.pdf
    • http://mesotects.com/wp-content/plugins/formcraft/file-upload/server/content/files/16110096e3ab32---64727713702.pdf
    • http://orgue-chantepie.info/FCKeditor/upload/file/64371316591.pdf
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1610db254a4ca1---banetexixufegafiwegibimu.pdf
    • https://www.alpha-dynamics.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1607da53448efb---vibupebololu.pdf
    • https://thejasmineway.net/wp-content/plugins/super-forms/uploads/php/files/7v6s1uavq6ftcgstd1gbva76ru/5607879925.pdf
    • http://xn--80aaae7amexjfdlfdfg.xn--p1ai/files/file/20385973060.pdf
    • http://quick-thailand.com/images/uploads/file/7034320369.pdf
    • https://anmimar.com/royal/userfiles/file/zudebanovibebex.pdf
    • http://scuderieverdina.it/scuderia/userfiles/file/63920469389.pdf
    • http://www.medical-psychology.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1612fc47f453cc---87152090365.pdf
    • https://mysmartedu.com/uploadimages/files/11136278428.pdf
    • http://zamel2.pl/userfiles/file/kagopopadureboxorawuxixo.pdf
    • http://connect-senior.ch/uploades/userfiles/file/mojimikobom.pdf
    • https://marblobathware.com/app/webroot/img/files/buzowejes.pdf
    • http://www.oschouston.com/osc/wp-content/plugins/formcraft/file-upload/server/content/files/1608462578d6ee---60704008706.pdf
    • https://ezgoe.com/10005001208290177/ckfinder/userfiles/files/pujajovis.pdf
    • http://lideparts.com/userfiles/file/1630666936.pdf
    • http://pansophers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cb55b5a253e---62315552218.pdf
    • https://www.ayersworthglen.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d1d1afd44d3---46679282568.pdf
    • https://nikken-engineer.jp/export/sd205/www/jp/r/e/gmoserver/8/6/sd0748886/nikken-engineer.jp/fckeditor/upload/file/21192083261.pdf
    • https://www.justgym.co.za/wp-content/plugins/super-forms/uploads/php/files/6nb1hg46fdeloc6es3ebq3tolt/28718132808.pdf
    • https://ofertaromania.ro/ckfinder/userfiles/files/61115754423.pdf
    • https://clickkedai.com/userfiles/file/jijekitejusataf.pdf
    • https://dewalt-naradi.cz/media/upload/editor/file/zavuvas.pdf
    • http://edwardlankin.com/clients/86087/File/49494576432.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_off0000d96e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD96E 16792 bytes
font_01_sfnt_off0000f180.bin
50f2c7aaeea217efe50b95dd72bab9174baf9d8357d8acdd88488b76743470c9
pdf-font-stream PDF embedded font (sfnt) at offset 0xF180 17440 bytes
font_02_sfnt_off00011e54.bin
4d811628bfacdf1a5e9750f12e998b487c1a1481201ce97b6d2302fe3088ddb7
pdf-font-stream PDF embedded font (sfnt) at offset 0x11E54 10620 bytes