Malicious PDF — malware analysis report

Static analysis result for SHA-256 4cbc2dde4b251457…

MALICIOUS

PDF

85.0 KB Created: 2021-06-29 18:49:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 92cbcc9996ee18f14a9971237c6b8024 SHA-1: 58b29837930547b0bd6f54b93d4b4d6a61de79b3 SHA-256: 4cbc2dde4b251457ce60ffcb5c3005d159334f7fe49adbafd362c12b16a90b4d
156 Risk Score

Malware Insights

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

The PDF file contains numerous external URIs and link farms pointing to potentially compromised WordPress upload directories and disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. The document's structure and embedded links suggest it's designed to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://krisoc.ru/uplcv?utm_term=how+to+highlight+text+in+pdf+in+laptop
    • https://kolodezrus.ru/wp-content/plugins/super-forms/uploads/php/files/d0c0730c75a98810e36fde34892cb9db/6764164242.pdf
    • https://asiatravel.kg/wp-content/plugins/super-forms/uploads/php/files/1dc7d2bf5ab843e4e1095d6edcd8c4c0/fusulokojugedogu.pdf
    • https://eminencesolutions.in/resources/userfiles/file/78148044886.pdf
    • http://nuyewpilot.academy/wp-content/plugins/super-forms/uploads/php/files/4e9f8722f1d19f1c1f45d3617e9fb429/32804377909.pdf
    • https://noukos.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160983d45e32e6---fijikeziwavekoleron.pdf
    • https://wsbtitan.com/images/file/tajepefikepe.pdf
    • https://www.criteriainvest.com.br/wp-content/plugins/super-forms/uploads/php/files/t3ealhluaqdr61q12jkmf6h4va/kutavo.pdf
    • https://associazionedynamica.it/uploads/file/21728154940.pdf
    • http://pvsystreports.com/wp-content/plugins/super-forms/uploads/php/files/2vq8eudavueq9p4nivojlt1d52/10609865632.pdf
    • http://arch-teh.com/pic/userfile/71682658833.pdf
    • http://kulturazebrak.cz/userfiles/67556727293.pdf
    • https://ubranni.com/uploader/files/41601708890.pdf
    • https://reifenscho.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609c18584891e---54830703396.pdf
    • http://www.molinoag.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607560c58a893---joxug.pdf
    • http://aahsclassof1978.com/clients/b/b6/b6117739535924054831d33ecd54b00a/File/fisezosisivamajada.pdf
    • http://trenermichal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160b7856a49efb---44855618005.pdf
    • http://liebherr-tr.com/userfiles/file/46109518549.pdf
    • http://gvs-russia.ru/admin/ckfinder/userfiles/files/61296931441.pdf
    • https://olterus.net/contents//files/pufugi.pdf
    • https://ocvirapuato.com.mx/wp-content/plugins/super-forms/uploads/php/files/224d93e37a5149461efa1796d769dace/58294891082.pdf
    • https://acgroupenterprise.com/userfiles/file/xisikigigobiruxarokebu.pdf
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ae459aabf04---61766739612.pdf
    • http://lapawan15.com/shop/fck_file/file/69951359483.pdf
    • http://bigyikesmedia.com/home/xtremweb/public_html/consultinstitute/web/upload/files/wetanodoforawajabapuzunik.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_off0000ea4d.bin
6ac31ac7e0f9a9c72826cddc9c4a624b0387b7a73c098f72d8bf3f69626c9a3b
pdf-font-stream PDF embedded font (sfnt) at offset 0xEA4D 10688 bytes
font_01_sfnt_off00010289.bin
2e980ba83d8058f41a2940733e9969bea0e9420d626d8b809b21339aa4d893c6
pdf-font-stream PDF embedded font (sfnt) at offset 0x10289 16908 bytes
font_02_sfnt_off00012e7d.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12E7D 16792 bytes