Malicious PDF — malware analysis report

Static analysis result for SHA-256 873009c61529f153…

MALICIOUS

PDF

85.2 KB Created: 2021-09-11 12:16:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 9393c14ddb77f6d191c88186ee98bed6 SHA-1: 3dfca9a4e085c8cecf6b80fb5f7a00eae88e3cc7 SHA-256: 873009c61529f153360ec0063a7c3773baabdb0b0ba992a2c2c3754d1f3cde70
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a large number of external links, many of which point to compromised CMS upload directories or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution through these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://inter-travel.hu/_user/file/90508829701.pdf In PDF document text
    • http://acecaalcoy.com/userfiles/file/dutivumuvevo.pdfIn PDF document text
    • https://xn--fct5g39pjpo.tw/upload/leakstop/files/83649950131.pdfIn PDF document text
    • http://vtaky.sk/media/file/69376282128.pdfIn PDF document text
    • https://karlholmbygg.se/UserFiles/files/danepulironatuwarotaje.pdfIn PDF document text
    • https://rdsdealers.com/ckfinder/userfiles/files/lejesurubedubanamatu.pdfIn PDF document text
    • https://eclipsetheaters.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138129d4f5b4---15196486147.pdfIn PDF document text
    • http://ttlengenharia.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613be04a598d1---48766641974.pdfIn PDF document text
    • https://gloriamus.org/Uploads/userfiles/files/96448533730.pdfIn PDF document text
    • http://chelseafoodmart.com/uploads/files/64387877793.pdfIn PDF document text
    • https://fiscalonline.ro/app/webroot/files/userfiles/files/98600815707.pdfIn PDF document text
    • https://activsport.ro/userfiles/file/49269771068.pdfIn PDF document text
    • http://originalbau.hu/imagesfiles/befugukajorobagar.pdfIn PDF document text
    • https://www.formwork.co.uk/wp-content/plugins/super-forms/uploads/php/files/he30jspfjf5vapiovj56qganmj/zufunoxinapozima.pdfIn PDF document text
    • http://www.bash.cl/media/file/lewakodusuxiwumimovol.pdfIn PDF document text
    • http://serramentisiciliano.it/userfiles/files/muriniwozirak.pdfIn PDF document text
    • https://chogmai.org/ckfinder/userfiles/files/xexopulirizazorene.pdfIn PDF document text
    • https://iveducentar.com/uploads/assets/file/jofeteburosux.pdfIn PDF document text
    • http://studiolorenzoni.eu/userfiles/files/davevupumidemokini.pdfIn PDF document text
    • https://massagetheory.ca/wp-content/plugins/super-forms/uploads/php/files/46c3450442daf2732774acc0703f037b/52348176512.pdfIn PDF document text
    • https://salwangurugram.com/files/31095697791.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=come+eliminare+cronologia+google+su+androidPDF 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_off0000e7ba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7BA 17792 bytes
SHA-256: 3c9f50bf39ba12dea67a1ea77719dfc7c63c3bfffac6451e9199187403f3541d
font_01_sfnt_off0001162b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1162B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012e42.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12E42 10748 bytes
SHA-256: 8e2baa1b23db8cf7fdccd4968392530bb93d99b1989083e0d2c84a2d4a093167