Malicious PDF — malware analysis report

Static analysis result for SHA-256 854897727f158f41…

MALICIOUS

PDF

85.4 KB Created: 2021-09-19 01:07:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 8ef048dc0663f98498f8d0fe15393e1e SHA-1: 2214d83ad591e830a991e1bfb1b2d0a6873cad10 SHA-256: 854897727f158f4177e7bdaca59ccb2fefe63e6846304ba6e155e0e1d495df06
156 Risk Score

Malware Insights

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

The PDF contains a link farm with numerous URLs pointing to disposable hosting and compromised CMS upload storage, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. The primary attack pattern involves luring users through a malicious document to external, untrusted sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://ahxxzx.com/userfiles/202109/file/samuferebome.pdf In PDF document text
    • http://www.depomatrial.com/file/vopatiwoni.pdfIn PDF document text
    • http://minisadik-margaritka.ru/admin/ckfinder/userfiles/files/32261253488.pdfIn PDF document text
    • https://clearpatth.com/userfiles/file/bewonewovomuxajofasu.pdfIn PDF document text
    • http://conservationenergy.com/wp-content/plugins/formcraft/file-upload/server/content/files/16142e3f3817e9---wulaxadovazefotif.pdfIn PDF document text
    • http://tiszaikaland.hu/upload/file/30376952284.pdfIn PDF document text
    • https://infrastone.com/userfiles/files/12824759496.pdfIn PDF document text
    • http://fsgzb.com/upfolder/e/files/20210901060158.pdfIn PDF document text
    • https://www.ijestr.com/ckfinder/userfiles/files/40495412443.pdfIn PDF document text
    • http://bagpack.com.np/wp-content/plugins/formcraft/file-upload/server/content/files/1613dc57f0640a---69497055442.pdfIn PDF document text
    • https://wietsevoermans.nl/ckfinder/userfiles/files/50521837224.pdfIn PDF document text
    • https://sellos-mecanicos.com/wp-content/plugins/super-forms/uploads/php/files/741c3a6f725497c397f96da13a073320/kigatoguwurebir.pdfIn PDF document text
    • https://tungafilm.com/dorceiys/ckfinder/userfiles/files/61739873778.pdfIn PDF document text
    • http://bachtungcompany.com/upload/files/vijedifekebejiw.pdfIn PDF document text
    • http://borneneskontor-landsforening.dk/userfiles/file/xutexejodovodakuxituz.pdfIn PDF document text
    • http://esejsc.com/upload/files/65073366729.pdfIn PDF document text
    • http://hcwan.com/userfiles/file/85303147404.pdfIn PDF document text
    • http://brava-ekb.ru/userfiles/file/14141242460.pdfIn PDF document text
    • https://vmkstroi.ru/wp-content/plugins/super-forms/uploads/php/files/b72db49b4e998ee2201ae6a44f0c4a10/ninonobujodelapuxofofege.pdfIn PDF document text
    • http://mondoacquapiscine.com/userfiles/files/loderikobotawozuvudiwu.pdfIn PDF document text
    • https://tempatpasang.com/contents/files/99535174492.pdfIn PDF document text
    • http://chapraptti.org/userfiles/file/55782599790.pdfIn PDF document text
    • https://daynexweb.com/upload/ckfinder/files/geboviledibevogutibor.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=unicode+support+in+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_off0000e04d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE04D 10568 bytes
SHA-256: c6f765f19a997e9e47a66934e3b2c2d6fb12193f67335fc9f3df49ce97454e62
font_01_sfnt_off0000f88a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF88A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001109c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1109C 21352 bytes
SHA-256: 6c34de942565ac4d9cd4bad09f849879dc79dc8e25990edeaa83854a1a5bd2d4