Malicious PDF — malware analysis report

Static analysis result for SHA-256 5f52f39f67909ad6…

MALICIOUS

PDF

72.0 KB Created: 2021-09-24 17:21:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: ad4629c25808521c7d71fd7324f67b1b SHA-1: 358548e899ec83e2de1aa3ecbd7ce1e1f1cf636f SHA-256: 5f52f39f67909ad69889e5aa1571eb032160eb22436e313f76c9d9f3d2fc2ff6
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 it functions as a link farm, with many embedded URLs pointing to potentially compromised or disposable hosting sites. The document body is heavily obfuscated, preventing a clear understanding of its specific lure, but the overall structure and URL analysis strongly suggest a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://phannhan.vn/files/usersfiles/files/koxidojimivinagikere.pdf In PDF document text
    • https://raljob.com/userfiles/file/95680943243.pdfIn PDF document text
    • http://www.logistiekverbeteren.nl/ckfinder/userfiles/files/jisek.pdfIn PDF document text
    • http://besttailor.info/ckfinder/userfiles/files/52353320042.pdfIn PDF document text
    • http://aroma-es.red/yamituki-n/uploads/files/suxirisoxipora.pdfIn PDF document text
    • http://neurooperations.com/ckfinder/userfiles/files/34965412903.pdfIn PDF document text
    • https://siphouse96.com/wp-content/plugins/super-forms/uploads/php/files/84c65eb981f5e71beeafc00389522864/rugarofifedax.pdfIn PDF document text
    • http://gopherandsquirrelcontrol.com/admin/images/file/81627716278.pdfIn PDF document text
    • http://dianacb.cz/userfiles/file/6008665865.pdfIn PDF document text
    • http://sadvita.lt/pav/file/towuse.pdfIn PDF document text
    • https://valgott.com/images/userfiles/file/98691891746.pdfIn PDF document text
    • http://www.nationaalgolfcongres.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16147d72062c28---96506131710.pdfIn PDF document text
    • http://bibrka-school.org.ua/ckfinder/userfiles/files/vipolopomasi.pdfIn PDF document text
    • http://bizwd.com/wp-content/plugins/formcraft/file-upload/server/content/files/161300c141b5bd---gitijabu.pdfIn PDF document text
    • http://www.anclupnapoli.it/userfiles/file/zigovolepanolulenud.pdfIn PDF document text
    • https://toocapen.com/files/losere.pdfIn PDF document text
    • https://tmtteks.com/files/15494659763.pdfIn PDF document text
    • https://cursosadistanciayonline.com/medios/files/89896451107.pdfIn PDF document text
    • http://angelojrobles.com/admin_initial_test/userfiles/file/wukologubuvuxada.pdfIn PDF document text
    • http://theonejsc.com/userfiles/file/wikabomure.pdfIn PDF document text
    • http://mopi.eu/ckfinder/userfiles/files/4862094789.pdfIn PDF document text
    • https://drainscovers.com/wp-content/plugins/super-forms/uploads/php/files/34933d5207dd07834d0a3548b77d6741/fenokanelilobed.pdfIn PDF document text
    • https://bawwabatrizq.com/userfiles/file/solexefuzesopufike.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=system+data+flow+diagram+examplePDF 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_off0000b340.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB340 18024 bytes
SHA-256: cece297372e4fc9c400d2c7373a2cdc1331f457c18c366539518a59d03f43437
font_01_sfnt_off0000e0d7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0D7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f8ee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8EE 11112 bytes
SHA-256: 0b4ae763a5eba47afd85e1de1afa99e5c62709aa33a11bb7b64d6f723679d0ff