Malicious PDF — malware analysis report

Static analysis result for SHA-256 b42b8a8853660921…

MALICIOUS

PDF

76.6 KB Created: 2021-09-21 22:31:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 1e760b154258c71d62bcb1bccfe32d1a SHA-1: 9bfbdf452ce2c4b221fe436f7f80d487da13d7b2 SHA-256: b42b8a8853660921355497c329bd827b1e45fd7ac3af25b3d552d41eb107f001
156 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. No scripts were extracted, but the structure and URL patterns are consistent with a malicious PDF dropper.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://oniceh.ru/uplcv?utm_term=car+stunts+3d+mod+apk PDF link annotation
    • http://mariautonoleggiomarsala.it/userfiles/files/10946527283.pdfIn PDF document text
    • https://beeshark.ro/app/webroot/files/userfiles/files/25747857414.pdfIn PDF document text
    • http://joyandwowbook.com/upload/file/sinowikemukiwuzivilabu.pdfIn PDF document text
    • http://nhuaduongnhapkhauaz.info/upload/files/91797605764.pdfIn PDF document text
    • https://miamivanservice.net/wp-content/plugins/formcraft/file-upload/server/content/files/16145a8f9e0303---18793747444.pdfIn PDF document text
    • https://centar-znr-zop.hr/wp-content/plugins/formcraft/file-upload/server/content/files/161458e7f85380---18885236494.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141914b1086e---fejogagol.pdfIn PDF document text
    • http://kfgame.snailgame.ru/upload/files/20210912065546.pdfIn PDF document text
    • https://sieuthigo.vn/upload/ck/files/83307794092.pdfIn PDF document text
    • https://xn----8sbcehyodmtf1czh.xn--p1ai/userfiles/file/26234840982.pdfIn PDF document text
    • http://canoto.us/Images_upload/files/60430092652.pdfIn PDF document text
    • http://gamboeng.com/assets/ckfinder/userfiles/files/47439643830.pdfIn PDF document text
    • http://hzbmsj.com/images/upload/File/nuwofumovukubatelapa.pdfIn PDF document text
    • https://sluganarodu.org/userfiles/files/vogarubip.pdfIn PDF document text
    • http://motovelo-nmsk.ru/userfiles/file/koraxodego.pdfIn PDF document text
    • http://mondoacquapiscine.com/userfiles/files/lelinolixijim.pdfIn PDF document text
    • http://www.stallionreadymix.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/161339d8bd03d3---xonojapow.pdfIn PDF document text
    • https://littleitalypizzany.com/nbloom/fckuploads/file/79562407984.pdfIn PDF document text
    • https://ixiu-23.com/uploads/files/202109061110337413.pdfIn PDF document text
    • http://www.lukoilmarine.com/ckfinder/userfiles/files/lenosagagupopu.pdfIn PDF document text
    • http://covina.crazyrockinsushi.com/uploads/files/felit.pdfIn PDF document text
    • http://sfipl.in/userfiles/file/35167329237.pdfIn PDF document text
    • http://irodori.kir.jp/files/file/68196193154.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_off0000bdd1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBDD1 10676 bytes
SHA-256: 1d09d0db3b15f51898792ae176c55b1a78aa6b8c111fbe0ccd5a1c2183d71638
font_01_sfnt_off0000d659.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD659 21404 bytes
SHA-256: c04c2a35d63fa41b610e7ab59ca68121d0ba43a413cdd3f4b7c5a36bb77ec812
font_02_sfnt_off00010d19.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D19 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1