Malicious PDF — malware analysis report

Static analysis result for SHA-256 cdc2b54c357c2bf8…

MALICIOUS

PDF

80.1 KB Created: 2021-10-04 20:42:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 8e1ebc25b231a8bd7f1af067324dbf18 SHA-1: 0d22ce7e1414f0c89b7521cb5bd68fcba5839745 SHA-256: cdc2b54c357c2bf835126b8533059f46e3712682919a3ec33e9f0adbde1f1677
156 Risk Score

Malware Insights

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

The ML classifier and ClamAV detection strongly indicate maliciousness. The PDF contains numerous links to external websites, many hosted on compromised CMS platforms or disposable domains, suggesting a link farm designed to redirect users to malicious content. The presence of external URIs and the overall structure point towards a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://bk.knu.ac.kr/ckfinder/userfiles/files/3926222655.pdf In PDF document text
    • https://luatsubienhoa.com/upload/ck/files/mupizanur.pdfIn PDF document text
    • http://scarpatti.com/files/relilakonovoroxi.pdfIn PDF document text
    • https://espiber.cl/images/uploadedimages/file/mexapamepujakesego.pdfIn PDF document text
    • http://thomas-zigon.de/images/file/30489860516.pdfIn PDF document text
    • https://tamtam.com.ua/wp-content/plugins/super-forms/uploads/php/files/d223062d61af24474f24c02bbcb887f3/dusafiwenepo.pdfIn PDF document text
    • http://specialcats.nl/media/files/danugiganixuwikotubi.pdfIn PDF document text
    • https://hotelritariccione.it/wp-content/plugins/formcraft/file-upload/server/content/files/16146cc1ecfd4e---28996329007.pdfIn PDF document text
    • http://themultifold.com/wp-content/plugins/super-forms/uploads/php/files/jv4b3991ha4cl8viq8srsr2a81/zujomufokakeruvokukeje.pdfIn PDF document text
    • https://kiofruits.com/admin/uploads/files/pefaritefekimujovepa.pdfIn PDF document text
    • https://ocloud.millionserenity.com/images/upload/files/zekoz.pdfIn PDF document text
    • http://mfplus.ba/wp-content/plugins/formcraft/file-upload/server/content/files/1613d5ede4ed11---zanatokebafop.pdfIn PDF document text
    • http://cungcapluonech.com/upload/files/zamogori.pdfIn PDF document text
    • http://thuonghieutoancau.vn/uploads/files/32163361335.pdfIn PDF document text
    • https://growlocals.com/wp-content/plugins/super-forms/uploads/php/files/100734f920de9028d3c23677e4f11c2b/linivetiruladutopupa.pdfIn PDF document text
    • https://mekongtransport.com/upload/userfiles/files/93119312107.pdfIn PDF document text
    • https://holycrosshealthcare.com/userfiles/files/51529616891.pdfIn PDF document text
    • http://goodmax.ru/i/files/22799922455.pdfIn PDF document text
    • http://fpempresa.cen.es/userfiles/files/57597788936.pdfIn PDF document text
    • http://kommunikator.nu/demo/userfiles/file///repuxepetona.pdfIn PDF document text
    • http://ljhalls.com/wp-content/plugins/super-forms/uploads/php/files/fecddb874ebbd0f228ec53673252d242/merimabe.pdfIn PDF document text
    • http://cleversystems.ru/userfiles/file/66909564640.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=the+birds+online+freePDF 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_off0000d2dd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD2DD 18644 bytes
SHA-256: 087341abc663850d65609654e32401656963e75de976ba618a1e130ad500bc9c
font_01_sfnt_off000103bb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103BB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011bd2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11BD2 10296 bytes
SHA-256: a580b4aa37af9548339a4cfb507fdde165772a7f709fc83c10d9dc43fdeb455e