Malicious PDF — malware analysis report

Static analysis result for SHA-256 7583b35322c479ae…

MALICIOUS

PDF

81.8 KB Created: 2021-09-07 14:49:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 238dfb144ec43b18b43215a5d5515c26 SHA-1: 9ece709b1eda6d7ebf71a4aa80a899a21d02943f SHA-256: 7583b35322c479ae0db0c2ef220dcaa63a6c662bba361e1bc31378afa845f1d5
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate the document functions as a link farm, directing users to numerous external websites, many of which appear to be hosted on compromised WordPress installations or disposable domains. The presence of 'utm_term' in URLs suggests an attempt to track user interactions, common in phishing campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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://archism.ru/uplcv?utm_term=trenchless+technology+journal+pdf PDF link annotation
    • http://condosworld.com/abisol1/userfiles/files/84409144639.pdfIn PDF document text
    • http://basyapiemlak.com/yukleme_klasoru/userfiles/file/liwimafitofapawut.pdfIn PDF document text
    • http://www.hkqi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16116b611b87b2---dororudinus.pdfIn PDF document text
    • http://zaun-produzent.de/userfiles/file/lamixezagogapamopodaze.pdfIn PDF document text
    • http://www.nandomoraes.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16074b9286d6ba---fumifatubemefag.pdfIn PDF document text
    • http://byecook.com/ckupload/files/9723143157.pdfIn PDF document text
    • http://beloezoloto.ru/userfiles/file/bodolidupefimut.pdfIn PDF document text
    • http://ffarchitettura.it/userfiles/files/juzutukawomivakex.pdfIn PDF document text
    • https://soba05.org/wp-content/plugins/super-forms/uploads/php/files/894600d60c3558a5df80f0981d09891c/3323703244.pdfIn PDF document text
    • https://cungcapthitdetuoi.com/app/webroot/files/images/pages/files/vagobimikilipog.pdfIn PDF document text
    • http://ottuk-e.org/userData/board/file/totufarozilimeteri.pdfIn PDF document text
    • http://t-eamplus.de/web/editor/files/15983696817.pdfIn PDF document text
    • https://www.hotel-restaurant-plainfaing.fr/ckfinder/userfiles/files/makejisiw.pdfIn PDF document text
    • http://amwordpress.org/wp-content/plugins/formcraft/file-upload/server/content/files/1606ea2b610af9---50349782120.pdfIn PDF document text
    • https://postscriptproductions.com/wp-content/plugins/formcraft/file-upload/server/content/files/16128d67c555f9---56852662160.pdfIn PDF document text
    • http://rosesrealtyhomes.com/userfiles/files/xukuzot.pdfIn PDF document text
    • https://www.dyna-tech.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1608f35ec514ec---85383450168.pdfIn PDF document text
    • https://hps-gruppe.com/wp-content/plugins/super-forms/uploads/php/files/600b9jpmekatd5bi98ftqkctqi/bejafijiguzubekeza.pdfIn PDF document text
    • https://higher-reason.com/wp-content/plugins/super-forms/uploads/php/files/vqet8dfhehuoo3rukt94hk8m9j/getigesuwatemimi.pdfIn PDF document text
    • https://amesmedicalservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086aaa112e5c---70317077579.pdfIn PDF document text
    • http://www.icareonline.net.au/ckfinder/icare/files/tesuvasovedujomuwuluj.pdfIn PDF document text
    • http://ne-moloko.ee/wp-content/plugins/super-forms/uploads/php/files/2fc1937d43b08185fb699fd99402e8e0/16198849350.pdfIn PDF document text
    • https://wrd13.com/force/file/wafaguzagoposolidederodin.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_off0000d910.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD910 11116 bytes
SHA-256: ff357e538097b463fea6bb12e694a5728bdaa96efd9d0d3bc27f87a986dad944
font_01_sfnt_off0000f2c8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2C8 18204 bytes
SHA-256: 7bd3d40900bda83898bfaf755cc729a720b65c592c6700d4bdc98d4fa1d17bdd
font_02_sfnt_off000121b9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x121B9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1