Malicious PDF — malware analysis report

Static analysis result for SHA-256 f5737d3ccdbf8d8e…

MALICIOUS

PDF

74.8 KB Created: 2021-10-10 19:11:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: 1b397a21fad2926521e893d9134b6d41 SHA-1: d541035fdc6825bfcf4f163b54795d119ed74750 SHA-256: f5737d3ccdbf8d8e87a19b967ca5f4db36cb513239d71b579ce0c38cc24355a9
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, and exhibits characteristics of a link farm pointing to compromised WordPress sites. The embedded URLs suggest an attempt to redirect users to potentially malicious content, likely for phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and numerous external links indicate a malicious intent to lead users to external, untrusted resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://wastran.ru/uplcv?utm_term=top+idle+android+games PDF link annotation
    • http://hattrick-sports.com/wp-content/plugins/formcraft/file-upload/server/content/files/161571fe93203f---zinud.pdfIn PDF document text
    • http://hzbaoyan.com/images/upload/File/giwonewavunapudafikelod.pdfIn PDF document text
    • http://thecargonepal.com/userfiles/file/xosesugexedorovizavonudew.pdfIn PDF document text
    • https://xn--pssa17sw71b.tw/upimages/files/92232116046.pdfIn PDF document text
    • http://wangguanhardware.com/userfiles/file/rovidajemorudoxatoxefa.pdfIn PDF document text
    • https://namhunglogistic.vn/site/files/xipuxerexoxunefelubexu.pdfIn PDF document text
    • http://thanhcongtechtra.com/upload/files/jonijinaboxajis.pdfIn PDF document text
    • https://beautifulhairstore.com/upload/files/lolugezad.pdfIn PDF document text
    • http://livestocktool.com/d/files/zoxuvoxanevusapoleb.pdfIn PDF document text
    • https://phase1acoustics.com/wp-content/plugins/formcraft/file-upload/server/content/files/1615451e50bac1---77896645151.pdfIn PDF document text
    • http://linyuepharm.com/upload/files/99224924434.pdfIn PDF document text
    • http://hoteldanang.vn/uploads/images/files/pifukeronupavol.pdfIn PDF document text
    • http://hyundaihungthinh.com/uploads/images/files/74402573310.pdfIn PDF document text
    • https://m-audio.vn/img-m-audio/files/disudikevitipenes.pdfIn PDF document text
    • http://www.mmd.ntou.edu.tw/ckfinder/userfiles/files/91694890369.pdfIn PDF document text
    • http://ekorepetycje.eu/Upload/file/60877960985.pdfIn PDF document text
    • http://woykoff.hu/upload/file/82644219923.pdfIn PDF document text
    • http://aytekinpolatel.com/image/files/regizidukaropubokulu.pdfIn PDF document text
    • http://thai-apsproducts.com/file_media/file_image/file/59352809600.pdfIn PDF document text
    • http://seattledesis.com/fckeditor/file/23829020597.pdfIn PDF document text
    • http://onlytech-tunisie.com/userfiles/file/43285609361.pdfIn PDF document text
    • http://barrarioservicos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16159ebd1aed30---kunezodikoj.pdfIn PDF document text
    • https://jerseyshorepirates.com/userfiles/files/lebapaginisamuzovizamudul.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_off0000c13d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC13D 17100 bytes
SHA-256: f4c0635c665516eb69e686a71f77ed3e132e45b465ffe18695bf7a7c005e6bb4
font_01_sfnt_off0000ed89.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED89 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000105a0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105A0 10600 bytes
SHA-256: 28a67cff564c0f43c0e0a64a0f7416d5b598153540688585aa63e128303e1726