Malicious PDF — malware analysis report

Static analysis result for SHA-256 99bc6114aa73c1b1…

MALICIOUS

PDF

82.1 KB Created: 2021-08-10 00:28:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 0af4e4144a59b70dc51b69ef882aba33 SHA-1: c4069476176a3a9e54a1a9aecd826da3792f743e SHA-256: 99bc6114aa73c1b10691e729d74779bb4b97183f423e794d64a1b742f827cab7
156 Risk Score

Malware Insights

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

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links pointing to compromised or disposable domains, indicating a link farm designed to redirect users to malicious sites. The presence of these links suggests an attempt to lure users into downloading further malware or engaging in phishing activities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9937

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://getampedmag.com/ckfinder/userfiles/files/jilutadofugolisezu.pdf In PDF document text
    • http://begemot-rus.com/uploadfiles/file/2021061602463373499.pdfIn PDF document text
    • http://schnauzermountainminiatures.com/clients/17729/File/jekevuxar.pdfIn PDF document text
    • https://ltgtrends.com/wp-content/plugins/super-forms/uploads/php/files/e674b7713ebba0f299b9f41bd55a407f/65433663203.pdfIn PDF document text
    • https://zweiund40.com/wp-content/plugins/super-forms/uploads/php/files/g30tlg2arjh51j7jfgrooe5iso/54451966134.pdfIn PDF document text
    • http://ankurgroups.com/userfiles/file/18475996498.pdfIn PDF document text
    • http://strelnicebudejovice.cz/userfiles/file/41484103863.pdfIn PDF document text
    • https://goldenparadisestsimons.com/wp-content/plugins/super-forms/uploads/php/files/8ce364da1960864515364121b5b8cbe7/17113661762.pdfIn PDF document text
    • https://bykevin.com/wp-content/plugins/super-forms/uploads/php/files/dd0b5a76a9037fc1583ffbd438c265be/dajugorireraxibimawoxit.pdfIn PDF document text
    • http://sun-green.de/ckfinder/userfiles/files/10240560040.pdfIn PDF document text
    • http://saludocupacionalpso.com/home/wp-content/plugins/formcraft/file-upload/server/content/files/160f254c256d1b---gutolakolupizozamaguto.pdfIn PDF document text
    • http://www.melodypods.com/wp-content/plugins/formcraft/file-upload/server/content/files/160834ab58a41e---davixamikadulo.pdfIn PDF document text
    • http://forresterfamilyreunion.com/clients/c/cc/cc72bfd2512333311cc1ef5a4fdef90f/File/sizuwij.pdfIn PDF document text
    • http://alpanelektrik.com/depo/sayfaresim/file/14457503173.pdfIn PDF document text
    • https://valserve.in/web/k/main_admin/ckfinder/userfiles/files/paninekateje.pdfIn PDF document text
    • http://gnatowski.pl/attachments/file/60576073265.pdfIn PDF document text
    • http://brighterhealthcare.co.uk/wp-content/plugins/super-forms/uploads/php/files/oqeaou98mkkqqkte3p0l60i3bm/kuxalu.pdfIn PDF document text
    • http://windcampus.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c4eb90cf8c9---73398952296.pdfIn PDF document text
    • http://www.truca-taoules.com//ckfinder/userfiles/files/84019099299.pdfIn PDF document text
    • https://bodwellassociates.com/wp-content/plugins/super-forms/uploads/php/files/45e71048b6fcc1e6073fcb52535457c8/lorafuzotugoluzivapekuw.pdfIn PDF document text
    • http://xn--54-dlcdkamdj4btild5b.xn--p1ai/ckfinder/userfiles/files/95453304409.pdfIn PDF document text
    • https://www.heracles-hotel.eu/wp-content/plugins/super-forms/uploads/php/files/ctupomrtsv52sl6t1bf6i973nd/jununipazuxapunuvi.pdfIn PDF document text
    • https://ottopianos.nl/files/getegagufevowe.pdfIn PDF document text
    • http://xn--b1ahhafccpgkb2bxo.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/5bc18539b7e2be42dc5bb5954fbd7580/newerenawoledakotaropof.pdfIn PDF document text
    • http://www.recetasyconsejos.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a5e3c609d34---xomoxafune.pdfIn PDF document text
    • https://aplusadvance.com/naver_editor/data/file/domebomixinasugupuka.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=how+to+measure+flatnessPDF 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_off0000defe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDEFE 16616 bytes
SHA-256: 8466000d393508e241941a94da68ce580d8c72bad7606550d7fff732628e32d1
font_01_sfnt_off00010a32.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A32 10460 bytes
SHA-256: 4d7222280dc1458cfa1350a467be3083b879251ce3cfc94fefe3db060db75128
font_02_sfnt_off000121fc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x121FC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1