Malicious PDF — malware analysis report

Static analysis result for SHA-256 44e73dbbd3592ac3…

MALICIOUS

PDF

97.4 KB Created: 2021-06-29 20:58:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 52f515683e8a399f3a2b8d092cd6f425 SHA-1: 76a77442e8b161909d794b201b4bf89ea33a2902 SHA-256: 44e73dbbd3592ac3ca8551d2ebfabdb7c995d62e652cc66554606e1638ea2d0e
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, directing users to multiple compromised websites hosted on disposable domains. The PDF structure and embedded URLs suggest it is likely used in phishing campaigns or to distribute further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9806

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 http://www.k-24.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607fb2192814e---wavimakifemivitolelixe.pdf In PDF document text
    • http://candientushinko.com/images/file/mufalef.pdfIn PDF document text
    • https://genesislighting.net/wp-content/plugins/super-forms/uploads/php/files/93c3e305fefbd71d392ba0e48632a4b3/30085029799.pdfIn PDF document text
    • https://hosvagyok.hu/userfiles/file/73340021654.pdfIn PDF document text
    • http://nacyc.jp/Upload/file/7982239659.pdfIn PDF document text
    • https://planet-for-events.de/userfiles/file/36363481629.pdfIn PDF document text
    • http://bobhendrix-law.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/sejule.pdfIn PDF document text
    • https://unicornproduction.gr/wp-content/plugins/super-forms/uploads/php/files/ffdce3367817b86432832ef6d3c9dd56/36068860351.pdfIn PDF document text
    • https://ecobox.eng.br/wp-content/plugins/super-forms/uploads/php/files/j5cfmd3ubdet8stlqpjaqd235t/30834691061.pdfIn PDF document text
    • https://martybermanassociates.com/wp-content/plugins/super-forms/uploads/php/files/c6384783be27ee021a9fcc322aa41953/21423366628.pdfIn PDF document text
    • https://plagij.at/ckfinder/userfiles/files/98394662510.pdfIn PDF document text
    • http://www.platformliften.info/wp-content/plugins/formcraft/file-upload/server/content/files/1609f05bea59c8---41912951222.pdfIn PDF document text
    • http://fontanarosaserigrafia.it/userfiles/file/kaxobilofagipel.pdfIn PDF document text
    • http://haumeaonline.com/userfiles/file/wigojorovamefexa.pdfIn PDF document text
    • http://sotel-perm.ru/site/file/xojomezopikavumo.pdfIn PDF document text
    • https://avgdesign.com/userfiles/file/49179368519.pdfIn PDF document text
    • https://aftaplan.com/works/peepsparty/html/upload_files/file/pokodufobu.pdfIn PDF document text
    • http://jullien38.com/ressource/site-image/files/luxekekapedisofudabu.pdfIn PDF document text
    • http://penzionklara.cz/userfiles/file/51990437118.pdfIn PDF document text
    • http://www.oknookna.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160706e59ecb96---sokufelikerisukili.pdfIn PDF document text
    • https://growlocals.com/wp-content/plugins/super-forms/uploads/php/files/e56a57d1ffea94fe825db639eba9f199/20349306281.pdfIn PDF document text
    • https://capecoralliving.com/media/file/laletudaronarufuzudogi.pdfIn PDF document text
    • https://ols.lighting/wp-content/plugins/super-forms/uploads/php/files/c0799c00757828bb52929b13969a6ffe/rodosaxoxobo.pdfIn PDF document text
    • https://razvozka24.ru/wp-content/plugins/super-forms/uploads/php/files/90b376be1b078577a4ab22e836fe490b/biteleredarosukogafefit.pdfIn PDF document text
    • https://muguet.fr/sites/default/files/file/26519307462.pdfIn PDF document text
    • https://zemiigori.com/uploads/file/59067903354.pdfIn PDF document text
    • https://mithermomix.com.mx/wp-content/plugins/super-forms/uploads/php/files/477237e3f0fd2c49e7be8dc6cdca8ef2/botosa.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=maplestory+how+to+level+up+fastPDF 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_off00011a86.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A86 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001329d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1329D 10616 bytes
SHA-256: 84c9e94dd6f917166dbc8f6fb40905384d9e1712a3c79e79692b880d0a6a66bb
font_02_sfnt_off00014b32.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14B32 17208 bytes
SHA-256: 88ca417668bfffc81dc5d545c1ea932832d05cf88d5e63ae6275155fe071726f