Malicious PDF — malware analysis report

Static analysis result for SHA-256 7c518214c5735abe…

MALICIOUS

PDF

79.4 KB Created: 2021-09-08 01:01:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 28bb549836df85e0ffed304b69d2de30 SHA-1: ca025b79884af8c382bd53a357bcc4cdf111e630 SHA-256: 7c518214c5735abeb0f162d4024572dbf6b832eeb807b03e3ff4f50fe61f1df1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is a PDF that contains numerous embedded URLs, many of which point to compromised websites or disposable hosting, suggesting a link farm used for phishing or malware distribution. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were directly extracted, the PDF structure and embedded URIs are indicative of techniques used to lure users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://crysiq.ru/uplcv?utm_term=nootropil+1200+ulotka+pdf PDF link annotation
    • https://cakenflowersonline.com/userfiles/file/rujufe.pdfIn PDF document text
    • http://www.halpellet.hu/userfiles/files/61222764377.pdfIn PDF document text
    • http://chenruichem.com/upload/files/rubefomapujovavovitanibe.pdfIn PDF document text
    • https://www.energetisch-therapeut-estie.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160983255812b2---puzelal.pdfIn PDF document text
    • https://adiwirawanbali.com/wp-content/plugins/super-forms/uploads/php/files/01a3aac5b7538de46c9615e07f3732ad/wimoja.pdfIn PDF document text
    • http://www.polni.si/Images/files/62428681478.pdfIn PDF document text
    • https://klairtransport.com/uploads/files/38862043312.pdfIn PDF document text
    • https://hse.tw/upload/file/40742579082.pdfIn PDF document text
    • https://gotoko.com/cmsv2/upload/files/48037999945.pdfIn PDF document text
    • https://beribuket.ru/wp-content/plugins/super-forms/uploads/php/files/e108d99a26934e1d595522d0f3101d6e/naderiwupajosivop.pdfIn PDF document text
    • http://chickenwild.com/upload/contents/images/images/39008658561.pdfIn PDF document text
    • http://mulroyenvironmental.ie/userfiles/file/xejoregizurida.pdfIn PDF document text
    • https://transcendenceit.com/wp-content/plugins/super-forms/uploads/php/files/5da825aa0863356d66a80049d165e94e/selariwebesasasulo.pdfIn PDF document text
    • https://capitaleny.com/wp-content/plugins/super-forms/uploads/php/files/18bcb7aa32a69ee5f22f1e80229da140/11628949175.pdfIn PDF document text
    • http://austria-ex.com/images/blog//file/fepaxat.pdfIn PDF document text
    • http://locthanhwindow.com/img_duhoc/files/64114387946.pdfIn PDF document text
    • https://eyestech.in/wp-content/plugins/super-forms/uploads/php/files/df8hdvmoqtfs7alnm6pa07v56v/65502665693.pdfIn PDF document text
    • https://www.auditek.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160e369efe1f2e---36871183230.pdfIn PDF document text
    • http://graphicyazd.com/ckfinder/userfiles/files/sopepadeveze.pdfIn PDF document text
    • http://antwerp-rentals.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b099b901d1---pesatozew.pdfIn PDF document text
    • http://unipell.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16089a67abba0a---mijex.pdfIn PDF document text
    • https://rmdschoolandcollege.com/wp-content/plugins/super-forms/uploads/php/files/c4pbngfv23cr6pru157li1m1n3/11538207473.pdfIn PDF document text
    • http://www.sport-konyv.hu/userfiles/file/verejuwaguzifanisubo.pdfIn PDF document text
    • https://frasertechno.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b24134a1d3c---49493654070.pdfIn PDF document text
    • http://crossfit28.com.s125853.gridserver.com/siteuploads/editorimg/file/18777962597.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_off0000d266.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD266 17484 bytes
SHA-256: b0b03be769587e14b20cf94ff9b538caddd1868ed3d2e4cf737382fed6a48883
font_01_sfnt_off0000ff6b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF6B 10548 bytes
SHA-256: 61065c70d000b32b2daaa413c3a960caf2c8231ebf6a39e0675c0a3b07b1c944
font_02_sfnt_off000117a3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x117A3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1