Malicious PDF — malware analysis report

Static analysis result for SHA-256 a42b0b5c264dc2dd…

MALICIOUS

PDF

74.5 KB Created: 2021-09-08 07:21:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 77fda16d7d9d2fd5d9ce6da81600c36c SHA-1: 7a15278fe2b0938eeaed73651a7c05280d37dd06 SHA-256: a42b0b5c264dc2dd76748ee7f3b050a9c47cd9857b91967bc7ab4d5cfeb08ef2
104 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and a significant number of external links, many pointing to compromised or disposable hosting. This suggests the document is designed to act as a link farm or for SEO poisoning, likely to redirect users to malicious content or phishing sites. The ML classifier strongly indicated maliciousness.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

Heuristics 6

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://billedbutikken.dk/articlefiles/file/36250367723.pdf In PDF document text
    • https://sidexsideaudio.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608c4b8c571f0---giputofikamoxano.pdfIn PDF document text
    • http://kino-cosmic.ru/sadm_files/1475821535.pdfIn PDF document text
    • https://iqmuseum.mn/uploads/files/81487567220.pdfIn PDF document text
    • https://sg-design.top/wp-content/plugins/super-forms/uploads/php/files/2d63b053a703913cd96a97448c6de21c/61130688900.pdfIn PDF document text
    • http://mp-journal.com/media/file/16531185080.pdfIn PDF document text
    • http://grafosaleservice.cz/images/fck_editor/file/munumezemikoleseve.pdfIn PDF document text
    • http://philipp-haberland.de/images/upload/file/giwiwulenebosapar.pdfIn PDF document text
    • http://adacu.org/userfiles/file/20210625093232.pdfIn PDF document text
    • http://rsst77.ru/upload/files/82282935979.pdfIn PDF document text
    • https://realimpacto.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a2d8e32fb42---29335984696.pdfIn PDF document text
    • https://lostsoulsmemorialnj.org/wp-content/plugins/super-forms/uploads/php/files/51da68238003e6980b524abd745e3b34/65725447887.pdfIn PDF document text
    • http://gold-carsales.com/js/upload/files/fatuvodo.pdfIn PDF document text
    • https://rjiminfra.com/wp-content/plugins/super-forms/uploads/php/files/d29b67fa2804416704f88b36a2256ae6/11204558044.pdfIn PDF document text
    • http://sushigonewildtogo.com/uploads/files/86628480368.pdfIn PDF document text
    • http://blessingsngo.in/userfiles/files/37710909155.pdfIn PDF document text
    • http://bahattinburyan.com/userfiles/file/46516778510.pdfIn PDF document text
    • https://nikoljski.com/ckfinder/userfiles/files/13282318382.pdfIn PDF document text
    • https://www.freshstartdigitalmarketing.com/wp-content/plugins/super-forms/uploads/php/files/edad45f1b69c8def8b24f5900e11af65/28116036798.pdfIn PDF document text
    • https://muzeumkonstancina.pl/attachments/file/29021247748.pdfIn PDF document text
    • https://mithermomix.com.mx/wp-content/plugins/super-forms/uploads/php/files/fb91d595b3cc20590f6cfcb378910599/32020463196.pdfIn PDF document text
    • http://phongthuyphatloc.com/luutru/files/jegexufezanedozewumen.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=dinesh+physics+book+for+class+11+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_off0000bdaa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBDAA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d5c1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD5C1 11020 bytes
SHA-256: 347742039f5600a4d17fa9733dd673c30f2a3951b55a5c7f684087f9e52edf29
font_02_sfnt_off0000ef1c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF1C 17428 bytes
SHA-256: 5da51850ec95dba721a717865c3def691c0b71a19c904828d15a4c64feed5e2d