Malicious PDF — malware analysis report

Static analysis result for SHA-256 aca0c59fbc662f43…

MALICIOUS

PDF

86.5 KB Created: 2021-09-08 21:10:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: b864fec0af850a0dcab0dc290be3c8ee SHA-1: af7c8aee5cf211d9fdd3d506e145ae5f4798c096 SHA-256: aca0c59fbc662f436557740027f03f463661daa98d77c3302fe040eea84c7b6c
96 Risk Score

Malware Insights

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

The PDF file contains a large number of embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier strongly flagged this PDF as malicious, and heuristics identified it as a link farm on compromised CMS uploads. The primary attack pattern is likely to lure users into clicking these links, potentially leading to phishing sites or malware downloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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 http://e-motyle.natura2000.pl/imgturysta/files/xigibi.pdf In PDF document text
    • http://didula.ru/img/file/446988579.pdfIn PDF document text
    • http://mgmkt.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1612f015a3ed25---71362061232.pdfIn PDF document text
    • http://debeleven.net/UserFiles/File/mowabugemudekam.pdfIn PDF document text
    • http://urgentcarepb.net/userfiles/file/lobumixu.pdfIn PDF document text
    • https://playgametoday.ru/wp-content/plugins/super-forms/uploads/php/files/52cd06fe5a6e0a3bbef1cccdfee3f9fc/19862589634.pdfIn PDF document text
    • http://work4shop.cz/userfiles/file/musurusabajimopusif.pdfIn PDF document text
    • http://atlonnuri.org/UpLoadImage/editer/files/boserinujizuwemipemub.pdfIn PDF document text
    • http://www.superior-inkjet.com/login/ckfinder/userfiles/files/36435074345.pdfIn PDF document text
    • http://ccswcd.com/userfiles/file/22948592904.pdfIn PDF document text
    • https://qualitycountscleaning.com/wp-content/plugins/super-forms/uploads/php/files/c89c953af86c55a40f6b23a3816b2171/60988857511.pdfIn PDF document text
    • http://fluorescent-training.com/file/badixafatezokezewaleju.pdfIn PDF document text
    • http://miyagi.chi-kara.net/Upload/files/18925915462.pdfIn PDF document text
    • http://jlsxjy.com/right/UploadFile/file///2021090610011473499.pdfIn PDF document text
    • http://hiredriver.com/uploads/assets/files/46500609049.pdfIn PDF document text
    • https://adian.eus/files/galeria/files/xozexitomob.pdfIn PDF document text
    • http://pileshoppen.dk/userfiles/file/zesamevebulawa.pdfIn PDF document text
    • http://bhhangkhong.com/upload/images/files/nikudinapetuduwokesaboj.pdfIn PDF document text
    • http://e-motyle.natura2000.pl/imgturysta/files/12037002780.pdfIn PDF document text
    • http://gadkowski.pl/repository/filemanager/file/77658839976.pdfIn PDF document text
    • https://clinicamanila.com/ckfinder/userfiles/files/27613422721.pdfIn PDF document text
    • https://marsanz.pl/uploads/fck/file/62588659663.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=meson+theory+of+nuclear+forces+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_off0000e733.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE733 10832 bytes
SHA-256: 82f3f89d6657dbfb2cc9ff639e633fa0a6d360c9ea09a1932abb02cf888aec06
font_01_sfnt_off00010035.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10035 19824 bytes
SHA-256: 29ade5d7986f1c2538a410428281bb2a7e76a6e5757e4fe558252d02a60c3a28
font_02_sfnt_off00013455.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13455 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1