Malicious PDF — malware analysis report

Static analysis result for SHA-256 aa4f51c5a59bc3e4…

MALICIOUS

PDF

92.1 KB Created: 2021-06-27 09:42:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 839bf1493d4b2c56b29bdf10e8039970 SHA-1: 84ae53884d1ca854b3c53c97eb30c99156760dd1 SHA-256: aa4f51c5a59bc3e4903cbca237cbe23f8bcb83acd76d060889d4813cee1e9d0f
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged by a machine learning classifier and ClamAV as malicious. The heuristic 'SE_FAKE_CAPTCHA' indicates the document presents a fake CAPTCHA or human verification prompt to the user. Several URLs extracted from the document point to compromised CMS upload directories, suggesting a potential distribution point for further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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
  • Fake CAPTCHA / human verification prompt high SE_FAKE_CAPTCHA
    Document displays a fake CAPTCHA or human-verification prompt — used to trick users into running commands or pressing keyboard shortcuts
  • 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.
  • 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://osullivanspressurewashing.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607fe4124218b---debufusoduxudemerizi.pdf
    • http://anhuishangbiao.com/upload_fck/file/2021-5-3/20210503105643385220.pdf
    • https://www.charroninc.com/wp-content/plugins/super-forms/uploads/php/files/8b7e95e1e34673b81a84e17d4ed83d7f/senovifizimalelugadubefa.pdf
    • https://questyme.ca/userfiles/file/27466290609.pdf
    • https://cananalimdar.com/wp-content/plugins/super-forms/uploads/php/files/nr82erpv2tj8okqkm0sadmav4l/64624711390.pdf
    • https://sharzh-ufa.ru/wp-content/plugins/super-forms/uploads/php/files/075a79704fd6faf2c620873052ad03a5/mareza.pdf
    • https://www.qlsny.com/wp-content/plugins/super-forms/uploads/php/files/01ae2b9079ea13a7a17742d1e5da09d1/4523473477.pdf
    • http://akicgiyim.com/userfiles/file/vomulewososep.pdf
    • http://almar-bus.pl/userfiles/file/tajaropupugala.pdf
    • http://wmehoa.org/clients/d/df/dff1b85474dadb967ea0c40f6d5e37f8/File/33241477609.pdf
    • http://domholidays.com/userfiles/file/35831180673.pdf
    • https://alianzatours.com/imagenes/file/wunofipixakalabupimuvuv.pdf
    • http://pansophers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c7a1738ed77---58192485236.pdf
    • http://informerfitness.com/wp-content/plugins/super-forms/uploads/php/files/a7f64852d4859c6e3dac19840b890d08/tubamaromane.pdf
    • http://location-appartement-venise.com/italie_documents/files/sederi.pdf
    • http://ehsclassof64.com/clients/b/bf/bfa5c4411462ceee4a19e543862d902c/File/92743033323.pdf
    • http://www.cargeacrew.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16094144bd51df---vodibo.pdf
    • http://botosani.ro/img/uploads/file/89885408859.pdf
    • https://kham.vn/userfiles/file/6105230884.pdf
    • http://escolacaritas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a2de5ae8def---kitasimobiledasajoli.pdf
    • http://shannonlakeestates.org/fck_images/file/28467028301.pdf
    • http://acril.ru/ufiles/files/karezujibujejus.pdf
    • http://visualpaint.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cf6e190693---39314370095.pdf
    • https://alfa-pechati.ru/wp-content/plugins/super-forms/uploads/php/files/3e0b843993792df411614386c6e1fd0c/79883899393.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=frontiers+in+cellular+and+infection+microbiology+impact+factor
    • 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_off0000fe3a.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFE3A 16792 bytes
font_01_sfnt_off00011651.bin
0cb48099557d82d943b324d8cdb40caa2cc57e88e3d6a78c4b59eb108ea36c9c
pdf-font-stream PDF embedded font (sfnt) at offset 0x11651 11292 bytes
font_02_sfnt_off0001306b.bin
6d79b89c9fb04c95dd0637827d80083ad12f3d4fb75289b48cfd964c9ac5b5dc
pdf-font-stream PDF embedded font (sfnt) at offset 0x1306B 19780 bytes