Malicious PDF — malware analysis report

Static analysis result for SHA-256 9c353fb828bb03ac…

MALICIOUS

PDF

87.8 KB Created: 2021-07-23 04:04:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 94d5f50a47c42d4c30892b36cbebdc3a SHA-1: c8d1f7054b10007a383ae387e955a0a47b37554e SHA-256: 9c353fb828bb03aca3fb4d0bf9b79f4ac094e6dcd53926fadc0518ef91b61709
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample contains embedded JavaScript, which is often used to exploit PDF vulnerabilities or redirect users to malicious sites. The presence of multiple links pointing to compromised WordPress upload storage and disposable hosting further indicates a malicious intent, likely to host or distribute malware. The ClamAV detection and ML classifier strongly support the malicious classification.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9986

Heuristics 7

  • 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.
  • 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 https://www.alertgy.com/wp-content/plugins/super-forms/uploads/php/files/7ea719eba9c7e971b2d84cbc49c67ccc/85616628327.pdf
    • http://otvorene-srdce.sk/userfiles/file/73539683543.pdf
    • https://klcmekatronik.com/ckfinder/userfiles/files/dutepakogivexup.pdf
    • http://www.gametimecatering.com/wp-content/plugins/formcraft/file-upload/server/content/files/160834f9083cb2---39222235886.pdf
    • http://sarahscupcakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bada5f534d6---18872756504.pdf
    • https://bk.knu.ac.kr/ckfinder/userfiles/files/bivemixip.pdf
    • http://averon.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160a6c27211d12---86666694887.pdf
    • https://www.hintonassociates.com/wp-content/plugins/super-forms/uploads/php/files/0b5e09d5bbd309645090dad02098e194/22077533649.pdf
    • https://spazmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b7ea638d502---pejefewowegujerowiw.pdf
    • http://smartcookieacademy.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085169270f42---wixasibazisivuxi.pdf
    • https://balance-global.com/wp-content/plugins/super-forms/uploads/php/files/ais0fkgf41cl883iqtnn8r21bc/68968019340.pdf
    • https://118highschool.am/wp-content/plugins/super-forms/uploads/php/files/5196f4512c3ac2d62991c25eb55a5f08/79389898740.pdf
    • http://inewbus.com/wp-content/plugins/super-forms/uploads/php/files/fq3tga183e1kokg5bsv357og65/58889789008.pdf
    • https://centrorevisionimonregalese.it/file/56122281798.pdf
    • http://greenmodels.ru/uploads/files/3345816043.pdf
    • https://discoverapartmentsforrent.com/wp-content/plugins/super-forms/uploads/php/files/6ed260cc6a8559cc735b41301a16f3ea/dobelevakojezuxixogasif.pdf
    • https://dudikom.pl/userfiles/file/xowetokitem.pdf
    • https://www.enviedecrire.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c853c5d5ce---90457340133.pdf
    • https://lerong.vn/wp-content/plugins/super-forms/uploads/php/files/25fcfe3d2b4bbae96760bca3a088701a/59086189446.pdf
    • https://beribuket.ru/wp-content/plugins/super-forms/uploads/php/files/53c96a7a291e8104be9f7c7972bcdabf/73276298735.pdf
    • https://magyar-logyogyasz.hu/fileok/file/61674742556.pdf
    • http://vilaportugal.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a82e22ed8c1---widivuwuboxa.pdf
    • http://xn--80ackbssfuieecff0e8c.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/p9hb40jubhaid89eftq77k9403/riwuriwepeko.pdf
    • http://pitin-akutsu.com/js/upload/files/87628741864.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=exercises+for+grade+6
    • 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_off0000f57e.bin
731bb84c5e81927c587b03c26a7a07f6b4179278a2f38f33d4a0513d848ebfa3
pdf-font-stream PDF embedded font (sfnt) at offset 0xF57E 10656 bytes
font_01_sfnt_off00010dda.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10DDA 16792 bytes
font_02_sfnt_off000125ec.bin
0fa69c8eab4d40c32bc7beb14ea7b149b06902932ee016a5b76c589995b9ee66
pdf-font-stream PDF embedded font (sfnt) at offset 0x125EC 16708 bytes