Malicious PDF — malware analysis report

Static analysis result for SHA-256 9cf5cf6fd3c07b9e…

MALICIOUS

PDF

78.9 KB Created: 2021-09-13 06:18:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 9ce7b235f1aa2fc551695c30967098c2 SHA-1: aaad663ed56fd9f8aa70199cc43f4ac89245e642 SHA-256: 9cf5cf6fd3c07b9ed60171a3ceb16ecb208ead78f220c862a553d24a95034d35
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains a large number of external links, many of which point to compromised websites or disposable hosting, indicating a link farm. The ML classifier strongly flagged this PDF as malicious. The presence of numerous URLs suggests an attempt to manipulate search engine rankings or to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 5

  • 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://smidgel.ru/uplcv?utm_term=how+to+install+chrome+os+on+android+tablet PDF link annotation
    • https://dienmayminhchau.vn/uploads/news_file/11190709041.pdfIn PDF document text
    • http://fornacedelia.it/userfiles/files/dadepegufabudawuze.pdfIn PDF document text
    • http://globalroomplus.com/bot/ckfinder/uf/files/80541050408.pdfIn PDF document text
    • http://tjsyjdq.com/v15/Upload/file/20219111759308959.pdfIn PDF document text
    • https://congtydaihai.com/upload/files/lovifikigegosedamep.pdfIn PDF document text
    • http://yourbuilding.ru/userfiles/files/jakefanuvedifafabupeso.pdfIn PDF document text
    • http://xn--80ackbssfuieecff0e8c.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/drr678k434m3su61o0708vin12/6133486485.pdfIn PDF document text
    • https://plentis.eu/ckfinder/userfiles/files/94036060604.pdfIn PDF document text
    • http://bowenlawmt.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/95799211192.pdfIn PDF document text
    • http://logo4you.dk/userfiles/file/5681262317.pdfIn PDF document text
    • http://namadagaskare.ru/ckfinder/userfiles/files/tovopemenimubosewuka.pdfIn PDF document text
    • https://vatlieutaphu.com/upload/files/56884054352.pdfIn PDF document text
    • http://abwclayton.com/uploads/files/sowumokezavonapuk.pdfIn PDF document text
    • https://www.swx.global/wp-content/plugins/super-forms/uploads/php/files/9bc4dd06b583ab59fc669d123deccffd/24259498681.pdfIn PDF document text
    • http://www.cerathai.com/image/upload/File/57000831579.pdfIn PDF document text
    • http://merwepizza.com/upload/file/fazukexamopimomilez.pdfIn PDF document text
    • https://socialacademy.gr/wp-content/plugins/super-forms/uploads/php/files/9394b2f7822c2616289d7654f8572c75/mezawavibonibipotanuled.pdfIn PDF document text
    • http://chapaconoticias.com/assets/ckfinder/core/connector/php/uploads/files/tafera.pdfIn PDF document text
    • http://revucue.com/ckfinder/userfiles/files/14656544292.pdfIn PDF document text
    • http://hodori247.com/uploads/files/36287858125.pdfIn PDF document text
    • http://m-s-g.ru/userfiles/files/8225450972.pdfIn PDF document text
    • http://birons.net/wp-content/plugins/super-forms/uploads/php/files/ffc78791db04fcf12d2091675e6157b7/12750287140.pdfIn PDF document text
    • http://toyotacri.com/userfiles/files/velane.pdfIn PDF document text
    • http://oskarmak.com/userfiles/file/kupevegifesu.pdfIn PDF document text
    • https://kaskad-74.ru/images/uploads/fosovunasidunudizobi.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_off0000cfe8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCFE8 17280 bytes
SHA-256: e9ffa0920d6ea437b3644dd153fba2974476fb8945dda6dcde4e25fb256bde14
font_01_sfnt_off0000fcb3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFCB3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000114ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x114CA 10852 bytes
SHA-256: 87578eeebc70d20a7fcb4d5c88d81b4b945b990c46a0e55b635e38973f0ac9f7