Malicious PDF — malware analysis report

Static analysis result for SHA-256 28afd4800329c637…

MALICIOUS

PDF

88.3 KB Created: 2021-09-15 10:05:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: d2bb9d0116be2061ace7a5942b2b337d SHA-1: 121017bdc15e1e37660b40e89cd0e702be1a127b SHA-256: 28afd4800329c637f2815c3a1ee55d1f91fca86b561f727e304ace1fcf2c9fb2
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm pointing to multiple domains, many of which are hosted on compromised CMS platforms or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and embedded URLs suggest it's designed to lure users to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://ita.kru.ac.th/ckfinder/userfiles/files/sulovapotabosusavakeli.pdf In PDF document text
    • https://www.popcaffe.it/wp-content/plugins/super-forms/uploads/php/files/23ebace3736135619c0351252f8dde4d/47983260384.pdfIn PDF document text
    • https://xn----7sbbg1ddpkdc.xn--j1amh/uploads/files/98981966977.pdfIn PDF document text
    • https://dedywiredja.com/wp-content/plugins/formcraft/file-upload/server/content/files/161355e97c97c2---kaliwudewuroti.pdfIn PDF document text
    • https://psystat.net/candyticket/uploads/page_images/files/50585559386.pdfIn PDF document text
    • https://gelblighting.com/userfiles/files/23712505037.pdfIn PDF document text
    • https://hospvetcentral.pt/site/upload/file/79385180738.pdfIn PDF document text
    • http://architettobotteonpierpaolostudioabacus.it/userfiles/files/34021000094.pdfIn PDF document text
    • https://lbjgold.in/ckfinder/userfiles/files/vekixojeketevo.pdfIn PDF document text
    • http://decorstore.eu/upload/file/1478394821.pdfIn PDF document text
    • http://snkpost.com/fckedit_file/file///20210906_2_32_35.pdfIn PDF document text
    • https://netiko.fr/img/Data/file/81212979521.pdfIn PDF document text
    • https://izharfoster.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141277aabbfe---59323556217.pdfIn PDF document text
    • https://cahayaapi1.com/contents/files/xixevumekof.pdfIn PDF document text
    • https://pingthye.com/userfiles/files/80443319726.pdfIn PDF document text
    • http://husplaza.hu/editor_up/vorijagijadalani.pdfIn PDF document text
    • http://gowowdeli.com/uploads/files/43196841908.pdfIn PDF document text
    • https://htijsr.com/userfiles/file/72438123933.pdfIn PDF document text
    • http://jdjcnc.com/upfolder/e/files/20210911032357.pdfIn PDF document text
    • https://pieseautocomenzi.ro/userfiles/file/1044454913.pdfIn PDF document text
    • https://samsungklima.net/upload/ckfinder/files/56771253277.pdfIn PDF document text
    • http://tysons-cafe.com/uploads/files/30416446454.pdfIn PDF document text
    • https://puertoestereo.com/wp-content/plugins/super-forms/uploads/php/files/7r4m7p8r3r9ld9je2fpc4gq6d3/sewone.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=track+my+phone+best+android+appPDF 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_off0000f339.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF339 11040 bytes
SHA-256: c5dac1fa6d84874b0f22e84fc978d6144f71aebaf3a9881cdbf6a9646533f0a3
font_01_sfnt_off00010c96.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C96 17996 bytes
SHA-256: 300ab987f20723496eaf45bee4229e43f4ce5b015b77c23ead5cf1aed7a76088
font_02_sfnt_off00013b2f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13B2F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1