Malicious PDF — malware analysis report

Static analysis result for SHA-256 f254a63bc2227538…

MALICIOUS

PDF

86.7 KB Created: 2021-09-20 05:49:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: f62a43931212c336d512c2e027d239a9 SHA-1: cca36722e7dc8fa6ebd969667ddd2e07b61489a0 SHA-256: f254a63bc22275383a92b126e9733495182e8843c62f67a0ba35c6c5f58ef44d
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many of which are hosted on disposable domains and utilize UTM parameters, suggesting a link farm designed to obscure the ultimate destination. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and heuristic firings point towards the exploitation of PDF vulnerabilities or social engineering to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://laborke.ru/uplcv?utm_term=convert+pdf+to+excel+offline PDF link annotation
    • https://mimpiindah88.com/contents/files/lobatugasoxasoti.pdfIn PDF document text
    • http://ruishikaishi.com/upload/content/files/2021/09/20210903035754.pdfIn PDF document text
    • https://artofsurfing.com/preview/ckfinder/userfiles/files/jatulafegadimogepowoliro.pdfIn PDF document text
    • http://www.mkkdigital.pt/wp-content/plugins/formcraft/file-upload/server/content/files/161416cb8baae1---jimebofuwogelux.pdfIn PDF document text
    • https://peiitw.com/Upload/ckeditor/files/rugabewitarepikesuzilus.pdfIn PDF document text
    • http://www.psoealora.es/ckfinder/userfiles/files/nadivemujanuwukira.pdfIn PDF document text
    • http://www.39koratmachinery.com/file_upload/files/xazazivaf.pdfIn PDF document text
    • https://acp-luxusingatlanok.hu/ckfinder/userfiles/files/gofaxu.pdfIn PDF document text
    • http://rzn-house.ru/upload/file/fatejoxoguzuwa.pdfIn PDF document text
    • https://webtechnocrats.com/upload/file/gedepotaboxexaxokug.pdfIn PDF document text
    • http://xn--80aadcnaeutgftohcogh8i8dsc.xn--p1ai/pict/file/87303557819.pdfIn PDF document text
    • http://designerhouse.ru/upload/files/29238629334.pdfIn PDF document text
    • https://mattress-leader.com/media/15775112922.pdfIn PDF document text
    • https://sunsetlearningcenter.com/userfiles/file/42408922711.pdfIn PDF document text
    • http://senvietsystem.com/ckeditor/upload/files/vakimunenalufososek.pdfIn PDF document text
    • http://www.luna1956.com/images/library/File/35310008709.pdfIn PDF document text
    • https://maydongy.com/wp-content/plugins/super-forms/uploads/php/files/i8m7fc29q46699qep53r7usoa4/32973532545.pdfIn PDF document text
    • http://www.synagoge-stommeln.de/ckfinder/userfiles/files/65525332028.pdfIn PDF document text
    • https://www.khaosanpools.org/ckfinder/userfiles/files/93649357644.pdfIn PDF document text
    • https://motty-etai-sharon.com/files/files/tanerifamebevofebosa.pdfIn PDF document text
    • http://firstcuwire.com/file_media/file_image/file/71067988804.pdfIn PDF document text
    • http://xn--80aatg4aaaddkhfhbf3evf.xn--p1ai/ckfinder/userfiles/files/detajibaxutinekusobosizop.pdfIn PDF document text
    • http://sozopolihills.com/userfiles/file/vudubozedadekugelum.pdfIn PDF document text
    • https://latrinquette.com/upload/editor/file/sajitapajabopemewusupaje.pdfIn PDF document text
    • 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_off0000f0b3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0B3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000108ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108CA 10484 bytes
SHA-256: 13ee74b291af1f7df1b9f061efa5a9d393086c7f3abb3af07088f1b399f22cd6
font_02_sfnt_off000120be.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x120BE 17092 bytes
SHA-256: 7f734fbd7c9e49c93b61932a2bd0de110a44835c660ef382fe71139d432869bc