Malicious PDF — malware analysis report

Static analysis result for SHA-256 c743391a5792c352…

MALICIOUS

PDF

80.8 KB Created: 2021-09-19 03:59:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 88f7d4581d50337ea90ed216184f8868 SHA-1: ecec5a3f14cde863c28b5eabde1e705ecc257ff0 SHA-256: c743391a5792c352c6038c4f08dca378841528be6ee1fab4f44767b43fcfb5cc
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, with several pointing to compromised WordPress upload directories, indicating a link farm designed to redirect users to potentially malicious sites. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. No scripts were extracted, but the structure and URL analysis are sufficient to infer the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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 http://originalavto.ru/userfiles/file/runilum.pdf In PDF document text
    • https://coil.hk/upload/files/wokaditutile.pdfIn PDF document text
    • https://www.nobleorthodontic.com/wp-content/plugins/super-forms/uploads/php/files/10830a8829185be6cfbbfb748ad6712a/kirotewirepej.pdfIn PDF document text
    • https://takarasushimn.com/userfiles/files/12966862597.pdfIn PDF document text
    • http://avvocato-callegaro.it/public/file/70875342739.pdfIn PDF document text
    • https://muzeumkonstancina.pl/attachments/file/88213378889.pdfIn PDF document text
    • http://sentezetutmerkezi.com/upload/ckfinder/files/24027417142.pdfIn PDF document text
    • https://optimuselearningschool.aels.edu/learning/site/images/uploadfiles/91028570595.pdfIn PDF document text
    • http://launensia.cz/ckfinder/userfiles/files/gusawotevubum.pdfIn PDF document text
    • https://copab.tn/216mag.svn/uploads/files/82396230371.pdfIn PDF document text
    • http://klusjesindex.nl/images/uploads/jorawufedipetujen.pdfIn PDF document text
    • https://tp-pos.com/uploads/image/files/70297418939.pdfIn PDF document text
    • https://home18.ru/wp-content/plugins/super-forms/uploads/php/files/675bbfcd8d4836df0f40dd9072f59813/41888531590.pdfIn PDF document text
    • http://kientrucphatloc.com/upload/files/defoz.pdfIn PDF document text
    • http://armiikrajowej36.pl/public/upload/ckfinder/userfiles/files/36178021950.pdfIn PDF document text
    • http://xn--2osv9pt2jfpt.com/uploadfiles/files/zosexenokijusikalagadape.pdfIn PDF document text
    • http://www.polni.si/Images/files/jamusi.pdfIn PDF document text
    • https://www.advids.co/wp-content/plugins/formcraft/file-upload/server/content/files/1613996d480b7e---62206404585.pdfIn PDF document text
    • http://ptaki.info/imgekoprojekty/files/jimutasadupuvodazex.pdfIn PDF document text
    • https://southafricapools.com/contents/files/lenud.pdfIn PDF document text
    • https://himalayanespresso.com/espresso_ckfinder/userfiles/files/59047138033.pdfIn PDF document text
    • http://timnhanhonline.com/upload/files/wudolazukupipezapuwotek.pdfIn PDF document text
    • https://elitteaccesorios.com/wp-content/plugins/super-forms/uploads/php/files/8vophlfdj9n6bdnu1d9g0dnpah/28067584594.pdfIn PDF document text
    • http://www.teaterskolen-efteruddannelsen.dk/ckfinder/userfiles/files/zowawiteronebiwipe.pdfIn PDF document text
    • https://wentworthre.com/wp-content/plugins/super-forms/uploads/php/files/6b583cdaee80b36377c9d189f7e41d75/fosawosatewikuxuduja.pdfIn PDF document text
    • http://ambartakip.net/belgeler/file/senigisunan.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=android+nfc+scan+credit+cardPDF 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_off0000d622.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD622 18148 bytes
SHA-256: 5f35448581564bd81684bae670140c4cc8d639c7e322469869df7b24cb5a10a8
font_01_sfnt_off000105dc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105DC 10404 bytes
SHA-256: 3ebdf312692784a57bc331fa1a55003ae8d5d4b79eade23c14fdd17b315c6645
font_02_sfnt_off00011d8f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D8F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1