Malicious PDF — malware analysis report

Static analysis result for SHA-256 4fc28d7192f6e5c6…

MALICIOUS

PDF

83.6 KB Created: 2021-06-26 13:42:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: 40350fe0fa05ea135e4f7ee9f46507bd SHA-1: 56b7ff5aa713554151c0ba7b826c003ba1145f2d SHA-256: 4fc28d7192f6e5c663c65cfc1b16a9e477fd24398a2ba88133b6397f3c50431b
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites or other disposable hosting, indicating a link farm designed to lead users to potentially malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://barcabianca.eu/upload/file/23087565980.pdf In PDF document text
    • http://librojuridico.com/aym_images/files/kitusad.pdfIn PDF document text
    • https://akapacha.com/userfiles/file/50999800489.pdfIn PDF document text
    • http://lavera.it/wp-content/plugins/formcraft/file-upload/server/content/files/16081532529649---17935657118.pdfIn PDF document text
    • https://borderpak.com/wp-content/plugins/super-forms/uploads/php/files/1d258d43face649116bed05d5ffc476d/10537791237.pdfIn PDF document text
    • https://tipresentoio.it/images/file/75887474872.pdfIn PDF document text
    • https://www.denisonlandscaping.com/wp-content/plugins/formcraft/file-upload/server/content/files/16083bb969b344---72938760946.pdfIn PDF document text
    • http://hevolta.com/upload/file/99250415884.pdfIn PDF document text
    • http://highgaincomposites.com/img/file/2021622225837.pdfIn PDF document text
    • https://unosms.us/userfiles/file/27111330333.pdfIn PDF document text
    • http://sotel-perm.ru/site/file/xobaturiwuxexizinived.pdfIn PDF document text
    • http://www.homefacelifters.com/wp-content/plugins/super-forms/uploads/php/files/16b0b8d9373bb0f0f2df9f145dc0ddbc/74869252318.pdfIn PDF document text
    • https://123kozijnofferte.nl/wp-content/plugins/super-forms/uploads/php/files/hbnacefhpsmn1ovreb0fs54j50/56169359282.pdfIn PDF document text
    • https://globalclassic.org/wp-content/plugins/super-forms/uploads/php/files/q0rkknrjsai1illfab58n4qcsi/dumawomal.pdfIn PDF document text
    • http://vimar.ua/userfiles/files/55982189971.pdfIn PDF document text
    • https://yidinfo.net/wp-content/plugins/super-forms/uploads/php/files/n2ssnsn4gjurh0ut4r1u3akavm/sibelazumipadusovibo.pdfIn PDF document text
    • http://topimmigrationlawyer.org/ckfinder/userfiles/files/55499275081.pdfIn PDF document text
    • https://www.focus.mu/wp-content/plugins/super-forms/uploads/php/files/c5aea0a8daa4162b747fec057fd7dac0/85530715341.pdfIn PDF document text
    • http://hrt-foto.hu/_user/file/bufifibamikevopib.pdfIn PDF document text
    • https://zlatartopalovic.rs//files/44796515474.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=this+is+not+soluble+in+waterPDF 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_off0000e59a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE59A 16936 bytes
SHA-256: c5020f35fe0fa3150a824db74741ff190ff47f385ad8503d722f8e9e71a12c8b
font_01_sfnt_off0001119e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1119E 10496 bytes
SHA-256: 2e5e15a4558f90704864c0977a01509469d947eeefbd741a4ed729406632040d
font_02_sfnt_off00012984.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12984 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1