Malicious PDF — malware analysis report

Static analysis result for SHA-256 a98c0aa582f02f13…

MALICIOUS

PDF

76.8 KB Created: 2021-09-06 19:54:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: fa0d8c373556ae2ea55743c2c92fcde1 SHA-1: f4be6eb2f0788686c8f26daddfb15b90ff581803 SHA-256: a98c0aa582f02f13efa3d4eee22f976fa1b0d8d3914dbf3b5d27f89dbf3ec8e2
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate the document contains a link farm pointing to compromised CMS uploads and disposable hosting, suggesting an attempt to redirect users to malicious sites. The embedded URLs and the nature of the heuristics strongly suggest a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://www.hintonassociates.com/wp-content/plugins/super-forms/uploads/php/files/7f82783991db7a111d59559317653539/95218922518.pdf In PDF document text
    • http://volkshilfe-vlbg.at/images/content/files/29799406298.pdfIn PDF document text
    • https://kalatranslation.co.uk/wp-content/plugins/super-forms/uploads/php/files/p9s99r6l1tpidh8k53vkj8g4bd/bixefuxivekebilapixixoxot.pdfIn PDF document text
    • http://yorktownhs1987.com/clients/57482/File/sumawusav.pdfIn PDF document text
    • http://virus-safe-zone.com/ckupload/files/wozijufafafixitiwutigeru.pdfIn PDF document text
    • http://alpanelektrik.com/depo/sayfaresim/file/89032323854.pdfIn PDF document text
    • https://qualitycountscleaning.com/wp-content/plugins/super-forms/uploads/php/files/f4753dcc1e3a795efc57ce99daea2ea7/xekufamidonedatarisusuna.pdfIn PDF document text
    • http://anhuishangbiao.com/upload_fck/file/2021-4-29/20210429041855208408.pdfIn PDF document text
    • http://ophirtonhotel.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1607758cb90ba2---desaputemoxovezokinerabox.pdfIn PDF document text
    • https://inlandautorepairmurrietaca.com/wp-content/plugins/super-forms/uploads/php/files/dd61bc79a0e2407ed486f716d65b2859/kikazo.pdfIn PDF document text
    • https://nguyenthelong.net/userfiles/files/pirumigoz.pdfIn PDF document text
    • https://ccaquebec.com/userupload/files/waxerulasovuxorolojir.pdfIn PDF document text
    • https://pharmnet.cz/ckfiles/files/files/49123733996.pdfIn PDF document text
    • http://atut-biuro.com/uploaded/file/9462005414.pdfIn PDF document text
    • http://2440027.ru/upload/file/39610367053.pdfIn PDF document text
    • https://plswa.com/wp-content/plugins/super-forms/uploads/php/files/1e2106a7596d917807a476e580b69364/xabozebaxomofaned.pdfIn PDF document text
    • https://www.hontoys.com.au/wp-content/plugins/super-forms/uploads/php/files/rsh9i5567m8a7qj3sp401vf8nr/27988719324.pdfIn PDF document text
    • http://www.ettermanenterprises.com/ckfinder/userfiles/files/66188485556.pdfIn PDF document text
    • https://www.harnoordesigns.com/wp-content/plugins/super-forms/uploads/php/files/jckt4mpa3q5iesorld75dikor6/leriwivebelu.pdfIn PDF document text
    • https://chmelo.hu/sites/default/files/file/kizomuru.pdfIn PDF document text
    • http://av72-reklama.ru/userfiles/file/162831030952e9d1aaa2225dd6bb16.pdfIn PDF document text
    • https://sportli.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/1608ace511f97d---94511565871.pdfIn PDF document text
    • http://modelkyujin.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608803175e7e8---tulan.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=ficha+biopsicosocial+para+secundaria+pdfPDF 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_off0000c613.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC613 18252 bytes
SHA-256: 2f54c3a56ead012b23e0d0c72c75a057a10fc87be5c618abfa2a43827d5fe81d
font_01_sfnt_off0000f481.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF481 10836 bytes
SHA-256: b99381be2b851856402d511ff83d0e14c10033c1f72dae8a61ea9bbb020249c1
font_02_sfnt_off00010d27.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D27 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1