Malicious PDF — malware analysis report

Static analysis result for SHA-256 f88c16f68d927956…

MALICIOUS

PDF

88.3 KB Created: 2021-07-14 07:41:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 17ad1e45a1a264e62a27bc551bbb9386 SHA-1: 2c6adf8370ca2a5880024de1c2ce25c76384a907 SHA-256: f88c16f68d927956e1af222a7c9ce06edbc97a6c764d41d85bf1e6eecb4bcc9e
156 Risk Score

Malware Insights

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

The file is a PDF that contains numerous external links, many pointing to compromised WordPress sites and disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or to redirect users to exploit kits. The presence of multiple PDF-specific heuristics related to URI and link farms supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://crysiq.ru/uplcv?utm_term=feet+and+feat
    • https://iescolumbus.org/wp-content/plugins/super-forms/uploads/php/files/824d7a3d316a831b957ca64d4a2679a1/bigefuxupoxam.pdf
    • https://eduinfinite.com/wp-content/plugins/super-forms/uploads/php/files/0593ead4b7cc52d5c128b36db01ac9b0/zebupijebamufo.pdf
    • http://salon-urody-bellis.pl/images/file/92705325159.pdf
    • http://lapenya.cat/imgjovesnaves/file/muminufonovifojoz.pdf
    • https://vickers-electronics.co.uk/wp-content/plugins/super-forms/uploads/php/files/b8360cb6e18d400dcb1594013d64a50d/fusesapirulaletejixe.pdf
    • http://www.belladermeestetica.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a9a6dda7e3d---55580306467.pdf
    • http://musicupclose.com/clients/f/f7/f7c291dfb329fbc33054893077acf627/File/99924536947.pdf
    • http://pobierzplik.pl/uploads/files/xonamud.pdf
    • https://formapolis.it/wp-content/plugins/super-forms/uploads/php/files/5637397cf9b4d1277848f4fbcc0107cb/vemubibipunojegotobolo.pdf
    • https://elbag.net/wp-content/plugins/super-forms/uploads/php/files/c1c7c1cfb735eb1f6a8c08f103f0547e/14036367816.pdf
    • http://goldcoil.com/uploadfiles/files/limofiwuzu.pdf
    • https://www.hauptsache.cc/wp-content/plugins/formcraft/file-upload/server/content/files/160b24903a0255---vokuwikawebidu.pdf
    • http://structurecreative.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a17e2b0d01f---10254775280.pdf
    • https://eyetracking.pl/userfiles/file/49002722721.pdf
    • http://change4best.ru/upload/file/86720617766.pdf
    • https://www.simcoerecovery.net/wp-content/plugins/super-forms/uploads/php/files/1csudcegdrgdfgtg0ea1c9ppj5/4728977450.pdf
    • https://web-sila.ru/wp-content/plugins/super-forms/uploads/php/files/d227ef08690f85e602825610b1776a22/76394132361.pdf
    • https://www.plsok.com/wp-content/plugins/super-forms/uploads/php/files/059910797ee9300d5db30ab06baec283/31017095798.pdf
    • https://xn--78-6kce7dfhb9dwb.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/daaaec1544a29e2ca05eca885376d3ae/49033341578.pdf
    • https://maidintown.co.uk/wp-content/plugins/super-forms/uploads/php/files/293aaf07f8e60cfdebcd27b153506233/wimunevutux.pdf
    • http://accurateverdicts.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a998a869fde---jurireg.pdf
    • http://qhs1978.com/clients/d/dd/dd8db5a278a7ad55a2ada34b8e38ebcc/File/67139242491.pdf
    • http://toyotarentcar.net/FileData/ckfinder/files/20210618_6B36AD499A423984.pdf
    • https://banghenails.com/upload/file/15447850599.pdf
    • 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_off0000f906.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF906 16792 bytes
font_01_sfnt_off0001111c.bin
ceeddfee8d28295bb3db80723768f955735e68bba7b60ecdf497bf2c52f8f805
pdf-font-stream PDF embedded font (sfnt) at offset 0x1111C 9796 bytes
font_02_sfnt_off000126a9.bin
dd2392ee4cc3522c0b364f09e9a3f69ca2cebb3182518f955b4346ade5daeaea
pdf-font-stream PDF embedded font (sfnt) at offset 0x126A9 17384 bytes