Malicious PDF — malware analysis report

Static analysis result for SHA-256 6395a70df7463b59…

MALICIOUS

PDF

137.3 KB Created: 2021-09-07 14:56:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 9e8da8e4c51301d4f598d1e5a3d14f9f SHA-1: d528bd3018228565e01cbb5f5829458de2d47112 SHA-256: 6395a70df7463b59ccfc96d6da14478c252c28031f1d329618528648f9a8ead1
156 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many of which point to compromised CMS upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. No scripts were extracted, and the document body was unreadable, so the primary attack vector appears to be the embedded link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9911

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 http://nhadep30giay.com/uploads/image/files/2393640231.pdf In PDF document text
    • https://fobiy.net/wp-content/plugins/super-forms/uploads/php/files/9028026672bf78888a94a99dbb638478/19706434667.pdfIn PDF document text
    • http://www.whirlpool-beachcomber.at/wp-content/plugins/formcraft/file-upload/server/content/files/160885ebf929c0---jukilukuwopepodalubokab.pdfIn PDF document text
    • https://goodline.by/userfiles/file/watusodagifa.pdfIn PDF document text
    • https://readxyz.com/wp-content/plugins/super-forms/uploads/php/files/ccafe6cea35ba30f9b3969df5f070081/pudifogexelat.pdfIn PDF document text
    • http://hart-metale.pl/gimnazjum/userfiles/file/55970185708.pdfIn PDF document text
    • https://www.rowtheerne.com/wp-content/plugins/super-forms/uploads/php/files/994a89f0aecd4c194c55ab33b7ce34cc/28239331030.pdfIn PDF document text
    • http://bestforfishing.com/wp-content/plugins/super-forms/uploads/php/files/bb2ad123f0d68c903632b64845ae8064/lubuwu.pdfIn PDF document text
    • http://aroma-es.site/yamituki-n/uploads/files/tevarun.pdfIn PDF document text
    • https://www.ibyservice.com/wp-content/plugins/super-forms/uploads/php/files/b0a0e9f62b85a7b7461f5c4c67cacf36/5443423129.pdfIn PDF document text
    • https://powermailer.in/userfiles/file/9517954390.pdfIn PDF document text
    • http://grandfiltr.com/files/file/vokitaxewonuwe.pdfIn PDF document text
    • http://runbo.net/upfiles/files/16292074469984.pdfIn PDF document text
    • https://alnahamgroup.com/userfiles/file/jipujun.pdfIn PDF document text
    • http://doyen.cc/images/upload/File/melivakokubewux.pdfIn PDF document text
    • http://color-gateway.com/userfiles/file/xevupifakapasex.pdfIn PDF document text
    • http://fontanarosaserigrafia.it/userfiles/file/tesimasareludanavufe.pdfIn PDF document text
    • http://lsphc.com/userfiles/file///nidojamobol.pdfIn PDF document text
    • http://www.hptindia.com/wp-content/plugins/formcraft/file-upload/server/content/files/16105edbaed52f---88265618498.pdfIn PDF document text
    • https://traveltokiev.com/wp-content/plugins/super-forms/uploads/php/files/5hafu399du7f04vbgdk4t4vc11/tilifigatiruwolotafemug.pdfIn PDF document text
    • https://designcoordinators.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608281aa2a889---tufemoxopesakepilape.pdfIn PDF document text
    • http://amsasecretariat.fr/userfiles/file/95711834292.pdfIn PDF document text
    • https://harpethvalleyhealth.com/wp-content/plugins/super-forms/uploads/php/files/e1d459eba3b534a5f3e57286cff7df56/13057014888.pdfIn PDF document text
    • https://www.bakkersvlaanderen.be/resources/plugins/ckfinder/userfiles/0/files/patodijevukugejinelafuf.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=pr%C3%A1ticas+de+gest%C3%A3o+de+recursos+humanos+pdfPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001a8b1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1A8B1 23220 bytes
SHA-256: 091ea298860afc8c391a5cd0e023b72509b1e28c16fce2b5464413a64bd2d9f1
font_01_sfnt_off0001e276.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1E276 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001fa8d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1FA8D 11568 bytes
SHA-256: a477484566ed80048bfbee954eb0be536a964574e0dbcf32bad1bdb4933a097c