Malicious PDF — malware analysis report

Static analysis result for SHA-256 637a1dbff9ffb4e6…

MALICIOUS

PDF

80.8 KB Created: 2021-09-06 18:08:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 1d8953a30cd1acbda04ed32b65265a33 SHA-1: 977be360484bc702b605153de80d08fee9ce341a SHA-256: 637a1dbff9ffb4e6883f48f74e745d454db5163d535c3d9faca7d9884308f9db
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF file was identified as malicious by ML classifiers and ClamAV, indicating it's likely a phishing or malware distribution lure. The document functions as a link farm, containing numerous URLs pointing to compromised websites and disposable hosting, designed to redirect users to malicious content. The presence of multiple external URIs and link farm indicators strongly suggests an attempt to lead victims to a malicious site.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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://noavarservice.com/ckfinder/userfiles/files/dirodivafumabigozav.pdf In PDF document text
    • https://smartbrand.ro/mm/file/fokipuxugaj.pdfIn PDF document text
    • http://www.musicmaestrodiscos.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160e6f0dff36e1---nitutigaxubenugixole.pdfIn PDF document text
    • http://master-br.ru/img/file/jurumirofam.pdfIn PDF document text
    • http://www.vitrierbxl.be/wp-content/plugins/formcraft/file-upload/server/content/files/1607ae0d7c0b61---36091333135.pdfIn PDF document text
    • http://moyamoya.center/images/hand_uploaded/files/8867730764.pdfIn PDF document text
    • http://www.bestlifepolicy.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1609225537c750---7234784371.pdfIn PDF document text
    • https://www.bouwenaaneensterkwerkgeversmerk.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607a700a42351---17369864363.pdfIn PDF document text
    • https://prcomponents.com/ckfinder/userfiles/files/nixolebiwebofufov.pdfIn PDF document text
    • http://prmakeup.com/Image/files/31835193196.pdfIn PDF document text
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/160908a9eaaf82---lakubefene.pdfIn PDF document text
    • http://lagunarent.lt/ckfinder/userfiles/files/68787154645.pdfIn PDF document text
    • http://bibikid.ru/upload/57376125759.pdfIn PDF document text
    • https://polskieplytki.com/wp-content/plugins/super-forms/uploads/php/files/01f1269e18e807f7c0696179a6bcd900/51508223883.pdfIn PDF document text
    • http://sinara.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606d514a235db---zaxedaz.pdfIn PDF document text
    • http://bubblesoflove.net/wp-content/plugins/formcraft/file-upload/server/content/files/1606d353597564---povaw.pdfIn PDF document text
    • http://pmdrecycling.com/wp-content/plugins/formcraft/file-upload/server/content/files/16074650a9b7e6---22400472754.pdfIn PDF document text
    • http://j-club.eu/userfiles/file/memasagut.pdfIn PDF document text
    • https://www.rogierstoel.nl/wp-content/plugins/super-forms/uploads/php/files/o156frok1pedo8iejf0de8t71o/niweginoxoji.pdfIn PDF document text
    • http://chokmanee.com/userfiles/file/nekugugudese.pdfIn PDF document text
    • http://makaifruits.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a664865a3ef---dilagirinuwafo.pdfIn PDF document text
    • https://autotrilogy.com/wp-content/plugins/super-forms/uploads/php/files/0115ab9c3c2d14affef8f447691ed929/33427366331.pdfIn PDF document text
    • https://anup.bo/images/files/87660307539.pdfIn PDF document text
    • http://antwerp-rentals.com/wp-content/plugins/formcraft/file-upload/server/content/files/16088d6bc93d97---95410186649.pdfIn PDF document text
    • https://irisapp.cn/uploadfiles/fckeditor/20210517/file/16212213062601.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=manual+lymphatic+drainage+exercisesPDF 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_off0000d8eb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8EB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f102.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF102 11152 bytes
SHA-256: a4ac0cf4dbceb3c9e3ec18444a343c549aa8b5080825752455e63f0914be57bf
font_02_sfnt_off00010aac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10AAC 16716 bytes
SHA-256: 744026635cb3e335eb50706348736f53b0e12c6e14136296195b87c042b06652