Malicious PDF — malware analysis report

Static analysis result for SHA-256 77b75867b0cfaa79…

MALICIOUS

PDF

86.9 KB Created: 2021-06-30 01:10:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: ed258f805829ca5f8caefcd3d294f69c SHA-1: 610e8665ce5444473de768f39d0d030f77bfc65a SHA-256: 77b75867b0cfaa793006b4cb2299a4e502ee8d28b00210a040d5c206c8e33e23
156 Risk Score

Malware Insights

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

The PDF file contains numerous links pointing to compromised WordPress sites, specifically targeting the 'formcraft' plugin's file upload functionality. The ML classifier and ClamAV detection strongly indicate malicious intent. The presence of a link farm on disposable hosting and the use of UTM parameters suggest an attempt to obscure the final destination and potentially engage in SEO poisoning or phishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://webmodels.studio/wp-content/plugins/formcraft/file-upload/server/content/files/160883c621e170---soroxa.pdf In PDF document text
    • https://lightupalife.org.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160854b8d0e20d---wezusib.pdfIn PDF document text
    • https://www.booster-p.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c672a895b67---84994581539.pdfIn PDF document text
    • http://longarmquiltacademy.com/fckeditor/userfiles/file/77262276030.pdfIn PDF document text
    • http://studioaba.net/userfiles/files/fulowetoresejoba.pdfIn PDF document text
    • http://ithaca1962.com/clients/41687/File/lenabidivejol.pdfIn PDF document text
    • https://singaporeroadshow.com/wp-content/plugins/super-forms/uploads/php/files/c8ab8ee82fe4fdac41cf1ecd1ae32e0b/86226459531.pdfIn PDF document text
    • http://gingerwooddesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076cfda95107---6124700267.pdfIn PDF document text
    • http://www.northeastmarquees.com/wp-content/plugins/super-forms/uploads/php/files/2efa7acf0dd30bcba491252589384635/vuzakom.pdfIn PDF document text
    • http://mountmedpharmacy.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160bacfa095c9b---82037335437.pdfIn PDF document text
    • https://www.tctnanotech.com/wp-content/plugins/super-forms/uploads/php/files/bf5468b493f02713c3da81810c6915cc/butufoxibabedut.pdfIn PDF document text
    • https://alkhairi.co.uk/wp-content/plugins/super-forms/uploads/php/files/73a8809293825f0a312636a68c3ee8c2/50805176226.pdfIn PDF document text
    • https://autosofortkauf.ch/wp-content/plugins/super-forms/uploads/php/files/72hrbbs1c8ngtiiamqt2o2uou2/98462643178.pdfIn PDF document text
    • https://www.sidertest.it/wp-content/plugins/formcraft/file-upload/server/content/files/160b245a9d8967---kemerawovagepomejekunalo.pdfIn PDF document text
    • https://primeodontorj.com/wp-content/plugins/super-forms/uploads/php/files/32b656c12c801045fe518f5057bea542/1950450947.pdfIn PDF document text
    • https://www.themeshcowork.com/wp-content/plugins/super-forms/uploads/php/files/c70c3046ec1b3bc5379b2ecc07cc049d/92524230141.pdfIn PDF document text
    • http://hitecds.com/userfiles/file/wajomit.pdfIn PDF document text
    • http://mirandatutoringcentre.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160ac91cdea1a2---76633470185.pdfIn PDF document text
    • https://mnlex.it/file/gebotedaxadug.pdfIn PDF document text
    • http://www.naturapreserved.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a2f219b7c2---32847053573.pdfIn PDF document text
    • http://theydeserveastamp.org/wp-content/plugins/formcraft/file-upload/server/content/files/160840d5fd2544---jaxifaz.pdfIn PDF document text
    • https://rmissio.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160c342a482429---5577339781.pdfIn PDF document text
    • https://www.kalirich.com/wp-content/plugins/super-forms/uploads/php/files/salfhcrees1elb5spqo8nq71b0/mururufemulasuxilalikam.pdfIn PDF document text
    • http://fitviewer.biz/files/file/sobekaveg.pdfIn PDF document text
    • https://dm288.rs/slicice/file/52174738947.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=eosinophils+0.60+meansPDF 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_off0000f126.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF126 17340 bytes
SHA-256: 25de0fe74f2c40c76fa6e9b55c1dbd41854842282c45c6edc84625ca5dffa341
font_01_sfnt_off00011e2c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E2C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013643.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13643 10660 bytes
SHA-256: e6db8cf5f44890043e3e870b32f9427dd9b16a4340cb2b55f0ab11c53538cf6a