Malicious PDF — malware analysis report

Static analysis result for SHA-256 a498891d425c6e16…

MALICIOUS

PDF

91.7 KB Created: 2021-09-02 18:02:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: daac9a828094ce2c890a4244bc3f89a6 SHA-1: d2cb8768e6deb7f403ca0fe4bf7b37d489f82ae4 SHA-256: a498891d425c6e16c56b6d98a7c0dd8b996b43487da7615f77649890a1bccdec
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF document 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 ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution. The presence of multiple external URIs and a link farm heuristic points towards an attempt to lure users to external resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9923

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 https://juvelyrikoscentras.lt/Files/file/14476737121.pdf
    • https://impariant-club.ru/wp-content/plugins/super-forms/uploads/php/files/60b1353b58cf0b77166c235f37f369bf/36058321594.pdf
    • https://bohemiamaestro.com/webpagebuilder/ckfinder/userfiles/files/bubaxuxobomemobegiduneg.pdf
    • http://donghozibistore.com/luutru/files/87617424166.pdf
    • http://nhs1980alumni.com/clients/878257/File/radosizowetewu.pdf
    • http://aweibel.com/Photo/file/62137735307.pdf
    • http://raunlarose.us/wp-content/plugins/formcraft/file-upload/server/content/files/1608f682ed7054---35215146060.pdf
    • https://nuregio.de/wp-content/plugins/formcraft/file-upload/server/content/files/1610a065a38cfe---dozajejesewenupojut.pdf
    • http://aptchasers.com/FCKeditor/userfiles/file/kewusewupufu.pdf
    • http://isagenixmakessense.com/ckfinder/userfiles/files/kijupubedukawavi.pdf
    • https://lcd96.ru/wp-content/plugins/super-forms/uploads/php/files/1067cfa974c22e44772497f0576f9b26/zudemusebepusovafe.pdf
    • https://rumahbaruku.com/contents//files/37745802662.pdf
    • https://www.mixedclass.com.au/wp-content/plugins/super-forms/uploads/php/files/lefdu2uscua0p1991c5g4en5bm/44967995723.pdf
    • http://baanpowertrain.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bc4759cda9d---92297813278.pdf
    • http://canyonmeadows.org/userimages/bomuvurebol.pdf
    • http://theeultimatenetworker.com/ckfinder/userfiles/files/nerav.pdf
    • https://sdyh.gr/wp-content/plugins/super-forms/uploads/php/files/sl2fskhla660n5d5b4h4eu0k67/sujani.pdf
    • http://mmckno2010.zkosuchdol.info/files/7761994344.pdf
    • https://eliteplacementagency.com/uploads/files/luzuterefuzelapaxanuruf.pdf
    • https://sibiucuratenie.ro/fckeditor/userfiles/file/52929530489.pdf
    • http://md-servicios.com/userfiles/file/55626456763.pdf
    • http://anapro.com/ckfinder/userfiles/files/7821687201.pdf
    • https://laihouston.com/wp-content/plugins/super-forms/uploads/php/files/0b9dbfdf302541afaf38cf9ff355bded/zimuxokiwu.pdf
    • http://sl-light.ru/design/img/upload/file/fapuwowemikotariwavo.pdf
    • https://coimbatorepressclub.com/FCKeditor/userfiles/file/36533537201.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=maths+formulas+for+class+11+pdf+free+download
    • 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e116.bin
837aa0424ea83aa125b61268e21d0fa9d459a3bafc32d935e2cbf384ad2aa30d
pdf-font-stream PDF embedded font (sfnt) at offset 0xE116 17780 bytes
font_01_sfnt_off0000fc62.bin
a806c97301eeebeea40d022d4c618c9dad25adb3319bb220e26f88a81ad573b6
pdf-font-stream PDF embedded font (sfnt) at offset 0xFC62 19052 bytes
font_02_sfnt_off00012e53.bin
143cc07805b0a5ff2e583975cb574f484bdaf3ddd0ed441cecc2893b52410c12
pdf-font-stream PDF embedded font (sfnt) at offset 0x12E53 11024 bytes
font_03_sfnt_off000147fc.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x147FC 16792 bytes