Malicious PDF — malware analysis report

Static analysis result for SHA-256 55bc85aef26c80e6…

MALICIOUS

PDF

84.0 KB Created: 2021-09-01 05:25:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: b368b6e9540f57666bbc0b1957ab5720 SHA-1: 4db2dc95dd1b730696cded208b8dd65f756999e1 SHA-256: 55bc85aef26c80e67a17b321d7971bc523c9452ca7e3e315c921a0fe6895033d
156 Risk Score

Malware Insights

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

The PDF document contains a link farm pointing to numerous URLs, many of which are hosted on compromised WordPress sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The document body is unreadable, but the heuristic findings and URL analysis are sufficient to assess its purpose.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://singaporenotarypublic.com/wp-content/plugins/super-forms/uploads/php/files/0686399a5637b81809c720c9007b8942/xezolipixagiwo.pdf In PDF document text
    • http://www.sunarozlem.com.tr/wp-content/plugins/super-forms/uploads/php/files/706s40001gmeqc05g9m0d573q1/69797422194.pdfIn PDF document text
    • http://urjabatteries.in/userfiles/file/60625820774.pdfIn PDF document text
    • https://www.sehersirin.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072caf9d2e3c---45485591650.pdfIn PDF document text
    • http://shethof.ch/cgi-bin/dynamisch/file/1139179529.pdfIn PDF document text
    • http://cariboohose.com/userfiles/file/54076210382.pdfIn PDF document text
    • https://levin-dent.ru/wp-content/plugins/super-forms/uploads/php/files/d083d4310f81d44f3525bf5a341d7e9e/begemawufaxeranoborez.pdfIn PDF document text
    • https://studio45.live/wp-content/plugins/super-forms/uploads/php/files/ccu868hp3drv0cv1llp1rfc74o/52911360588.pdfIn PDF document text
    • http://modelkyujin.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c99ff9084f---gilusepufebodi.pdfIn PDF document text
    • http://fujiya-burbank.com/uploads/files/45585636253.pdfIn PDF document text
    • https://www.couleurs-et-jardin.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160a32f14627f6---wovivowa.pdfIn PDF document text
    • https://teplitsyoptom.ru/wp-content/plugins/super-forms/uploads/php/files/5a0edf0038f6d865fcd78d1861dc3dc8/tozarozofewifer.pdfIn PDF document text
    • http://www.hkqi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d60293d8071---bizaxafomedopepozepufajat.pdfIn PDF document text
    • http://podiummoda.ru/userfiles/file/30057022450.pdfIn PDF document text
    • https://dineflon.com//files/25225693530.pdfIn PDF document text
    • https://vivaldiroberto.com/img/files/mediafiles/file/23102858776.pdfIn PDF document text
    • http://christmaslandint.com/userfiles/12167754734.pdfIn PDF document text
    • https://southernlightingsource.com/wp-content/plugins/super-forms/uploads/php/files/ed147eee151c66deebe6073098eec3e8/3284118253.pdfIn PDF document text
    • https://levin-dent.ru/wp-content/plugins/super-forms/uploads/php/files/73be9b8bde23d9a04d592eff9d0a4836/70106546899.pdfIn PDF document text
    • http://bawaconstructions.com/editorData/file/77890976575.pdfIn PDF document text
    • https://maydongy.com/wp-content/plugins/super-forms/uploads/php/files/hlk8mr2p4neh2rv9tep0lukvmf/dedukafetowelipeg.pdfIn PDF document text
    • http://araonline.hu/uploads/file/mozesasu.pdfIn PDF document text
    • http://cerrutistudio.eu/userfiles/files/revesazuj.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=arithmetic+definition+and+examplePDF 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_off0000dc09.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC09 10800 bytes
SHA-256: d5bc2ce0a3fa746d47351ae30b569ab372db191b55177fe9657a63efab39fca5
font_01_sfnt_off0000f4be.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4BE 20700 bytes
SHA-256: 2d492332576b988c588a7c03164879b7eb99862e7e34e30c5d718fd5c5c114e2
font_02_sfnt_off00012a41.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12A41 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1