Malicious PDF — malware analysis report

Static analysis result for SHA-256 5a4398162e634750…

MALICIOUS

PDF

94.1 KB Created: 2021-07-03 18:37:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 556f17c3c89307f05c603b44025bcdc5 SHA-1: 3d8ecc9791416aaeed014b8a992bf6f667785d08 SHA-256: 5a4398162e634750692d7efabe827b2e6f9ac2e0351b2089f1d220007352fc87
156 Risk Score

Malware Insights

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

The PDF contains a large number of embedded URLs, many of which point to compromised CMS upload directories or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The document body is unreadable, but the heuristic firings and URL analysis are sufficient to determine the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9989

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://ghalemdi.com/userfiles/file/34288288048.pdf
    • http://xn--h1aaebbkfib4a.xn--p1ai/sadm_files/lefekanezegodijirid.pdf
    • http://ferramentabelleggia.it/public/file/tamurulij.pdf
    • https://koratspring.com/upload/file/21775854007.pdf
    • https://www.yoursurveysurveyors.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160c7506ea1822---28956971164.pdf
    • http://ducthoaudio.com/upload/files/tulumejusulelafexonaze.pdf
    • https://tectrongim.com/uploads/files/tapiganiv.pdf
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b801af37e6e.pdf
    • http://drinkandshrink.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160b6200cc8504---95734863826.pdf
    • https://www.lenoir-elec.com/wp-content/plugins/super-forms/uploads/php/files/2ts7qe8nfpc801emh4te4kn4ng/tirijul.pdf
    • https://investainternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609387bb3d366---vewivasosamusaxofube.pdf
    • https://www.msolartop.cz/wp-content/plugins/formcraft/file-upload/server/content/files/1607f5eecb1684---57700181964.pdf
    • http://jointrilogy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160754d716cddd---71470492686.pdf
    • https://pavaniautismschools.com/wp-content/plugins/super-forms/uploads/php/files/5ngf8hfrdk5m03jgcvumctnbh5/47726897984.pdf
    • https://www.sblending.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160a0ce7a3fa65---94957388620.pdf
    • https://xn----8sbaavnccwq4am.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/960685ce51e9858de693e9beb9b6ed59/46352822965.pdf
    • https://derey.nl/app/webroot/files/userfiles/files/94077918887.pdf
    • http://www.holzbau-hoelzl.at/wp-content/plugins/formcraft/file-upload/server/content/files/1607e8c0b5704a---98457582965.pdf
    • https://www.ikedatosou.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608e6509d83e8---46657838812.pdf
    • https://borderpak.com/wp-content/plugins/super-forms/uploads/php/files/7eb4cb349ee95d31269b1f3e400530fd/kukiwomif.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=kb+of+c2h3o2
    • 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_off00010a55.bin
3defbde9bcfe010b7ed125b4c0630442ef382bc227c190ad880e07a51c8d3a97
pdf-font-stream PDF embedded font (sfnt) at offset 0x10A55 19028 bytes
font_01_sfnt_off00013c34.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13C34 16792 bytes
font_02_sfnt_off0001544a.bin
645560cf44d91c0798c5c8cc47301da46e5007114322b51b747ecea8e78c5a2f
pdf-font-stream PDF embedded font (sfnt) at offset 0x1544A 9956 bytes