Malicious PDF — malware analysis report

Static analysis result for SHA-256 b83104d278f0cc4d…

MALICIOUS

PDF

85.3 KB Created: 2021-06-27 08:29:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 756cb83631e5a3f04c6f6d571375e328 SHA-1: 7f2aef3527a9fe2ce5de05a215e493d23a48d174 SHA-256: b83104d278f0cc4d518c2dc44f1a49f087ad8959079d125cb4e3b1a30ad2282e
156 Risk Score

Malware Insights

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

The PDF contains a large number of embedded URLs, many of which point to compromised WordPress sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The document body is unreadable, but the heuristic firings and numerous URLs suggest a link farm designed to lure users to malicious content.

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 http://bestforfishing.com/wp-content/plugins/super-forms/uploads/php/files/c6a358b716062f8ee121aecf6836c1a7/47369206958.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084b7dfc1fb1---gotif.pdf
    • http://techsystem.gr/data/uploads/ckeditor/files/sipevifejufaselitokinig.pdf
    • https://glass-haus.ru/wp-content/plugins/super-forms/uploads/php/files/b46281c0cca206e05539be91268a5a58/norukevu.pdf
    • https://maloneslandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac0ec679a08---39560322408.pdf
    • http://counterreaction.net/wp-content/plugins/formcraft/file-upload/server/content/files/160c8b24b07295---64715196558.pdf
    • http://elitaliaweb.it/upload/file/89357194003.pdf
    • http://stroisvias.ru/userfiles/file/76863723098.pdf
    • http://casinodanmarkjackpot.dk/userfiles/file/sijabuz.pdf
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b634d749d90---6434438056.pdf
    • https://juvelyrikoscentras.lt/Files/file/kenulimu.pdf
    • http://odessahighschool1970.com/clients/7/70/70263b1be1b93b62200e198143f59f20/File/sokukesoreremen.pdf
    • http://ever-pioneer.com/upload/files/25386458511.pdf
    • http://mamnonlittlesun.com/upload/files/32653896954.pdf
    • http://kingspec.su/wp-content/plugins/super-forms/uploads/php/files/13qe4srvm44id5ilg6m7e483jo/74543942502.pdf
    • https://hanahana.vn/media/ftp/file/37873878785.pdf
    • https://engineeredrepinc.com/wp-content/plugins/super-forms/uploads/php/files/b4f3e666ea04cc89fa93e528c63d9f07/52699898357.pdf
    • https://www.fmworks.com.tr/wp-content/plugins/super-forms/uploads/php/files/a2li0ikg9250krrhffid28nilf/fuzitorusugigeva.pdf
    • https://whitelightdesign.com/wp-content/plugins/super-forms/uploads/php/files/b8e13c6c3663f5b90544900ff6612b52/65309617151.pdf
    • https://299-45.com/CKEdit/upload/files/33079864496.pdf
    • https://winston-woodward.com/wp-content/plugins/super-forms/uploads/php/files/aa3f1c94f63cc6b5ca5ba73707d60adf/94870344659.pdf
    • https://atlasautoglass.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d7a32eef005---80307051364.pdf
    • http://dancedynamicsla.com/clients/38740/File/6545528139.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=cute+henna+designs+for+kids
    • 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_off0000ec9a.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEC9A 16792 bytes
font_01_sfnt_off000104ac.bin
f7b4411f17a2e48870f23684bf1406ee832e00283e95a6dc1a30f60ee6d4dc88
pdf-font-stream PDF embedded font (sfnt) at offset 0x104AC 16404 bytes
font_02_sfnt_off00012f47.bin
3107a244bc3543d450ea12751bd8d594ed86e5f81e2bd5231b25da9044c8248d
pdf-font-stream PDF embedded font (sfnt) at offset 0x12F47 10808 bytes