Malicious PDF — malware analysis report

Static analysis result for SHA-256 834a4d30318f0563…

MALICIOUS

PDF

86.7 KB Created: 2021-07-05 04:17:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: ff18b6441d767ccffc5b6062699ce678 SHA-1: ab2aca194fc821ddb53841a443726cdec3d3d29a SHA-256: 834a4d30318f05631ad223c5e01a34f405e6fa57e9e8f50a031cc12912ef1019
156 Risk Score

Malware Insights

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

This PDF file was flagged as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous external links, many pointing to compromised websites or disposable hosting, suggesting it functions as a link farm to distribute malicious content or phish for information. The presence of multiple PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics further supports this, as these rules detect patterns commonly used in SEO poisoning and phishing campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9961

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://drafthe.ru/uplcv?utm_term=nursing+diagnosis+for+sickle+cell+disease
    • http://soepcentrale-dekeyser.be/userfiles/file/vivazalafovagedegegom.pdf
    • https://almondzwealth.com/administrator/imagetemp/file/85340074457.pdf
    • http://xn--80aaeiengkwpz6p.xn--p1ai/pub/file/welokeruvosilowibobek.pdf
    • http://relocationservicesgroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607873771760a---48131481676.pdf
    • https://mikepromedia.com/wp-content/plugins/super-forms/uploads/php/files/3cktfj62ba3s1uulhos52a4sh0/76211660949.pdf
    • https://travelselection.us/wp-content/plugins/formcraft/file-upload/server/content/files/160a2eed237117---defijokakatibasotiribu.pdf
    • http://4reality.cz/userfiles/files/83050705118.pdf
    • http://fixmyhelicopter.com/project-new/christianbook/upload_images/file/getasijiwilebuzasexivon.pdf
    • http://geologocarmignani.com/userfiles/files/zetiwogifutu.pdf
    • http://assushop.com/userfiles/assushop.com/file/wefijo.pdf
    • https://www.sadcmedia.com/wp-content/plugins/super-forms/uploads/php/files/81l0v99eg22tjm0vge8um4e23b/sawomuzusekesasube.pdf
    • https://agrotehholding.ru/wp-content/plugins/super-forms/uploads/php/files/6778b1be48046f31ff97f1a5c6012954/giraj.pdf
    • https://secolink.sk/userfiles/file/suzaxijodo.pdf
    • http://agataklimowska.pl/userfiles/file/lusudomiragavabon.pdf
    • http://garmagostaran.com/Upload/file/fimowekemovuke.pdf
    • http://www.marcelasemper.com/wp-content/plugins/formcraft/file-upload/server/content/files/160828ce78a02d---rewed.pdf
    • http://sakirnoopo.ru/wp-content/plugins/super-forms/uploads/php/files/8c429a75f7347723446bab436e06ae59/zovubinulimobev.pdf
    • https://heykidsletscook.info/wp-content/plugins/super-forms/uploads/php/files/0859568cdb98ec0510cfe36b066212dc/56718975763.pdf
    • http://aexpress.lv/index/images/up/file/rixebovejukabiselezagus.pdf
    • https://sellerflows.com/wp-content/plugins/super-forms/uploads/php/files/3af5132b660ff2042bdf09e089413aae/zomoz.pdf
    • https://www.straightmyteeth.com/wp-content/plugins/super-forms/uploads/php/files/363cf12b49ec5d181e4d53461bd9c63d/pixafulutusuvefinizaliti.pdf
    • https://deconkhoemanh.com/wp-content/plugins/super-forms/uploads/php/files/1c7r7os773o26p64f33gjbm5v2/38983431932.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_off0000f041.bin
1e6c01077764ee2d4c5af0d001ad6cf0a0b513bed02dafd0ef610bf738f944c4
pdf-font-stream PDF embedded font (sfnt) at offset 0xF041 17284 bytes
font_01_sfnt_off00011ce3.bin
e48197ae2a4b83795cdc8d75fd5710b1ea29bc1b3184d9ddc7186bf31cc488b8
pdf-font-stream PDF embedded font (sfnt) at offset 0x11CE3 10720 bytes
font_02_sfnt_off00013569.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13569 16792 bytes