Malicious PDF — malware analysis report

Static analysis result for SHA-256 43767151d16afd5e…

MALICIOUS

PDF

83.1 KB Created: 2021-09-13 13:48:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 4bf019ac13621d70018c327450db6de2 SHA-1: dacfdba30292cc8b65af700639f31ccec2b57b36 SHA-256: 43767151d16afd5e83d1daf45bdb786492cacadea30350bf06606ce6c6a10964
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected by ClamAV as Pdf.Phishing.Trojan and flagged by an ML classifier with high confidence. It contains numerous external URLs, many hosted on compromised WordPress sites or disposable domains, suggesting a link farm designed to redirect users. The PDF structure and embedded URLs indicate a phishing or malware distribution attempt, likely initiated via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://infrive.ru/uplcv?utm_term=how+to+set+android+keyboard PDF link annotation
    • https://kibledergisi.net/resimler/files/17553400256.pdfIn PDF document text
    • http://taispacedesign.com/upload/files/xifoni.pdfIn PDF document text
    • https://washlounge.in/ckfinder/userfiles/files/26274147381.pdfIn PDF document text
    • http://divapharma.com/uploaded/file/65012092212.pdfIn PDF document text
    • https://storage-in-motion.com/wp-content/plugins/formcraft/file-upload/server/content/files/161315c2c27ef1---nuxes.pdfIn PDF document text
    • https://unitedcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134e95325525---33596044612.pdfIn PDF document text
    • http://parvazyab.net/basefile/api203/files/19157562213.pdfIn PDF document text
    • http://www.wiz-fac.com/uploadImg/file/vipebago.pdfIn PDF document text
    • http://vititanon.com/user_img/files/sopiwit.pdfIn PDF document text
    • http://andrenickels.de/ckfinder/userfiles/files/mavujenabas.pdfIn PDF document text
    • https://www.syah.org/wp-content/plugins/super-forms/uploads/php/files/604e204920f0530d0ab56aa59dab2be8/20976091351.pdfIn PDF document text
    • http://modulobase.com/userfiles/file/gofaderimobosur.pdfIn PDF document text
    • http://eugensa.lt/app/webroot/uploads/userfiles/files/tifodukox.pdfIn PDF document text
    • https://kayakbranson.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b41e5c452b---93803418713.pdfIn PDF document text
    • http://aj-freight.com/ckfinder/userfiles/files/gofekipipajumibilosizobo.pdfIn PDF document text
    • https://www.rapn.ru/ckfinder/userfiles/files/sugexedukimovusegefafix.pdfIn PDF document text
    • http://fabriziocar.it/userfiles/files/50815824043.pdfIn PDF document text
    • http://tecs4.com/intranet/ckfinder/userfiles/files/datuzobusuj.pdfIn PDF document text
    • https://protum.se/file/31592979061.pdfIn PDF document text
    • http://i-p-p-c.com/ckfinder/userfiles/files/pekagajimokuzemofi.pdfIn PDF document text
    • http://mitcostruttori.it/userfiles/files/45308344428.pdfIn PDF document text
    • https://unicon-msk.ru/data/files/zitowoxiporitipe.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_off0000e183.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE183 17084 bytes
SHA-256: bae3c88fa15f37c882b1473598ba1626a408760a03af6603f2305474289bf81d
font_01_sfnt_off00010e4e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E4E 10620 bytes
SHA-256: 96beaf3f0fff2b3eb8ab582def1c6322807a68a5a4f6e6bb896d5057a6ad1cd6
font_02_sfnt_off000126c4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x126C4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1