Malicious PDF — malware analysis report

Static analysis result for SHA-256 f84c1b5fd43615c4…

MALICIOUS

PDF

91.0 KB Created: 2021-07-03 13:59:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d8c83a633a4203f644b397129ead19be SHA-1: 38bc8bcee9aa33d05063bd7b1b0ef68ff091ed71 SHA-256: f84c1b5fd43615c48d4bf2b6e6e1bfcb037e9443d87e1cc779bf562491a6711c
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to websites hosted on compromised or disposable domains, identified by heuristics like 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM'. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The document body is unreadable, but the link farm structure is sufficient evidence of malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://erex.hu/upload/file/jolegutemisa.pdf
    • https://noble-worldwide.com/wp-content/plugins/super-forms/uploads/php/files/0b8989904c9c91036739a0a8ad556a94/41180010131.pdf
    • https://www.bouldersudbury.org/wp-content/plugins/formcraft/file-upload/server/content/files/16076403eab951---gupisumejarixigimosidik.pdf
    • http://ankamet.com/userfiles/file/kejobubulubadeneked.pdf
    • https://chocoinmobiliario.com/wp-content/plugins/super-forms/uploads/php/files/cefabe7ec93811714a64384973146481/pajatokimi.pdf
    • http://614move.com/clients/4890/File/pubopuvu.pdf
    • http://antik-cafe-bergen.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b0dbe243b00---pisojumixekaduzejut.pdf
    • http://in-dapt.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a6beebe4fdb---forusobukivewelozararux.pdf
    • http://vitanova-cattery.com/upload/file/temiwanofoziwojuvenukofap.pdf
    • https://www.audifonosdoshoydos.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082640102d6b---zipozakok.pdf
    • http://afghansolar.com/userfiles/file/fupuxaladiwuxe.pdf
    • https://veterinarycarefoundation.org/userfiles/file/wawerixemuzojoluninu.pdf
    • http://ipvoicenj.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608513e750fbc---47794229171.pdf
    • http://www.everhouse.lt/wp-content/plugins/formcraft/file-upload/server/content/files/160877f4306fab---jaxuvidarururutid.pdf
    • https://www.kalirich.com/wp-content/plugins/super-forms/uploads/php/files/lokrc5ihuars88jc3pipsgsaf3/rerarogolo.pdf
    • https://manuscripthandler.com/userfiles/file/45448766484.pdf
    • http://woonhuislift.info/wp-content/plugins/formcraft/file-upload/server/content/files/160875ab636b85---80972194672.pdf
    • https://hospvetcentral.pt/site/upload/file/66242396320.pdf
    • http://sushi-belovo.ru/files/30812629430.pdf
    • http://ezibra.pl/upload//file/56265899842.pdf
    • https://www.alertgy.com/wp-content/plugins/super-forms/uploads/php/files/89744bef6d2a4d715d78029e6abb55a0/62837828103.pdf
    • http://christschoolblr.in/userfiles/file/98437705608.pdf
    • https://area34.info/wp-content/plugins/super-forms/uploads/php/files/dglnec2q66u6al0b2lr7hld5v6/92589010038.pdf
    • https://imapcb.org/wp-content/plugins/super-forms/uploads/php/files/17sjfmd1k42to34a30ud58c7v3/dovofovawifo.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=atdd+by+example+pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ffcc.bin
e15561c3f32c7847f18e6f4cc4488c04ccf828e91ae3ec5b190b1af4752a9907
pdf-font-stream PDF embedded font (sfnt) at offset 0xFFCC 18144 bytes
font_01_sfnt_off00012f58.bin
edded9007987b2de55c4f9b5e6c7f0892f33f0589482b2704fad134c7b4c64fb
pdf-font-stream PDF embedded font (sfnt) at offset 0x12F58 10412 bytes
font_02_sfnt_off000146c9.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x146C9 16792 bytes