Malicious PDF — malware analysis report

Static analysis result for SHA-256 c74485bbb00c714f…

MALICIOUS

PDF

95.1 KB Created: 2021-09-20 06:24:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: c5b3d9e84a7b9ca4df4558f285ed3f71 SHA-1: 497bfabdef116154f62c5acbbe9b4e418132ea69 SHA-256: c74485bbb00c714f2540eb6b2a460ff94efffa363a0287a9e617b9c71fb68d60
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains a large number of embedded URLs, many of which are hosted on compromised websites or disposable domains, indicating a phishing or link farm attack. The ML classifier and ClamAV detection strongly suggest malicious intent, likely to redirect users to malicious sites. No scripts were extracted, but the PDF structure itself is used to host and distribute these malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9935

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 https://synerhu.ru/uplcv?utm_term=the+croods+full+movie+free PDF link annotation
    • http://www.bewegeninarnhem.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16139ba077f381---16665667706.pdfIn PDF document text
    • http://veiligheidsslot.nl/ckfinder/userfiles/files/57138453587.pdfIn PDF document text
    • http://fitviewer.com/files/file/82717583418.pdfIn PDF document text
    • http://esteticka-stomatologie.cz/files/content/file/25740883229.pdfIn PDF document text
    • https://mountainbrookbuilders.com/home/mountain/public_html/ckfinder/userfiles/files/vewew.pdfIn PDF document text
    • http://weighlessthisyear.com/ckfinder/userfiles/files/defaxisirupukaxutu.pdfIn PDF document text
    • http://border-collie.ru/sites/default/files/file/topomexujopop.pdfIn PDF document text
    • http://woonhuislift.info/wp-content/plugins/formcraft/file-upload/server/content/files/1613b8fa94e5e4---8410873116.pdfIn PDF document text
    • http://mamolenasnc.it/userfiles/files/fubigi.pdfIn PDF document text
    • http://simonkuehner.de/gfx/userfiles/files/viritelojetefire.pdfIn PDF document text
    • http://xn--9n2bn9mz3aba29g44r4o0a.kr/fckeditor/userfiles/image/wedoxikenudivemikevejaje.pdfIn PDF document text
    • http://abwlargo.com/uploads/files/mojilobafakebosutimupu.pdfIn PDF document text
    • http://thaihotelsale.com/FileData/ckfinder/files/20210914_F88F076479479DF2.pdfIn PDF document text
    • https://wupaojichangjia.com/d/files/64024327042.pdfIn PDF document text
    • http://kelvista.lt/images/files/88638072531.pdfIn PDF document text
    • http://timnhanhonline.com/upload/files/katimekixadagizaj.pdfIn PDF document text
    • https://sharzh-ufa.ru/wp-content/plugins/super-forms/uploads/php/files/162cba58f35772c0cbc97ec429ce801f/xabejara.pdfIn PDF document text
    • https://cuichi177.com/uploads/files/202109010853001800.pdfIn PDF document text
    • http://stadion-zarya.ru/ckfinder/userfiles/files/72074132314.pdfIn PDF document text
    • http://ktcyy.com/ckfinder/userfiles/files/besijesu.pdfIn PDF document text
    • http://ssatripoli.org/userfiles/file/tegumowoz.pdfIn PDF document text
    • https://heks-tech.com/app/webroot/userfiles/files/febeku.pdfIn PDF document text
    • http://autofox.lt/ckfinder/userfiles/files/43989384731.pdfIn PDF document text
    • http://koopmankennedyfeller.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/90434889128.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_off000111c4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x111C4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000129d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x129D6 17488 bytes
SHA-256: 715a9c329ecf1e7daa83dec4db3ed7183230f1d0b2f01b81e0bcff0707b1cec8
font_02_sfnt_off00015769.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15769 10508 bytes
SHA-256: dc773e3413b9652eab28d9656d999958d5bc624b5d796b445e72ad2a90e6e997