Malicious PDF — malware analysis report

Static analysis result for SHA-256 b849fedd740e5516…

MALICIOUS

PDF

106.5 KB Created: 2021-06-25 12:42:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 1791f8e4f027fed3e5743f432d3671fe SHA-1: b3724bdf3961a19245d69abe7cf5929f84e96bcd SHA-256: b849fedd740e5516a41c98528451fffd1ba061ccf432d69d135a313ee7458a30
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many pointing to compromised WordPress sites and disposable hosting, indicating a link farm or phishing lure. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with malicious documents designed to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9902

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 http://kstarsmall.net/userfiles/file///88644632757.pdf
    • http://www.uvhk.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bcf0e1a13d3---24608296303.pdf
    • http://mistralizmiryonetim.com/uploads/file/jakevokufubomedub.pdf
    • http://dinskayarealty.ru/media/file/4886875677.pdf
    • http://matrixuniverzum.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160a38d864367c---jakatudu.pdf
    • https://globalclassic.org/wp-content/plugins/super-forms/uploads/php/files/btdi1dhfi8j0un9eanvu7aiaik/pazogatutapilome.pdf
    • https://sirikulsteel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16094a4708f62c---nefobos.pdf
    • http://vdgairconditioning.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16081268b423e3---dafek.pdf
    • http://www.majoriscambio.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16075c262c4ad7---dujefodusop.pdf
    • https://pavaniautismschools.com/wp-content/plugins/super-forms/uploads/php/files/rngf8vqe7ud5iaul142338g5ne/35094374813.pdf
    • http://www.klpreschool.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071c5c5210ba---82293454190.pdf
    • https://pikewallis.no/wp-content/plugins/formcraft/file-upload/server/content/files/160ba9c4f91517---37770682922.pdf
    • https://criteriacambio.com.br/wp-content/plugins/super-forms/uploads/php/files/mm9iqmk2ae9p8i66k0hj4thmvf/48660359172.pdf
    • http://bagiez.com/userfiles/file/nodonoz.pdf
    • https://xlspandoek.nl/userfiles/file/vesig.pdf
    • https://www.marthatrotts.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16080bcb42f2a3---48571680387.pdf
    • https://digidatadecolombia.com/wp-content/plugins/super-forms/uploads/php/files/789c336cb71c46bf01a47bb45098de96/96413928432.pdf
    • http://totalfinance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16090a35a23ab9---38110155121.pdf
    • http://trainternational.in/wp-content/plugins/formcraft/file-upload/server/content/files/16096007cee661---25194793523.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=who+does+meowth+evolve+into
    • 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 5

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001171c.bin
960f48564229e5836e32793435b2cbbc2e31bcec00bb7aab9c43e065ba001ef5
pdf-font-stream PDF embedded font (sfnt) at offset 0x1171C 3512 bytes
font_01_sfnt_off0001249b.bin
f44e1b7d18408819cff3a2774c5dd7541fe3e91a8a8b63f9257c514e28469824
pdf-font-stream PDF embedded font (sfnt) at offset 0x1249B 16636 bytes
font_02_sfnt_off00013c29.bin
c418aab25f02c9834e2a5cce756802f69eaaac03301fbc9c5d66c0222557bcc6
pdf-font-stream PDF embedded font (sfnt) at offset 0x13C29 10396 bytes
font_03_sfnt_off00015386.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x15386 16792 bytes
font_04_sfnt_off00016b98.bin
dfcda18a975496096d64121bf7a00216c8d5f961d85b07cc59e1a4c28fdd984a
pdf-font-stream PDF embedded font (sfnt) at offset 0x16B98 18556 bytes