Malicious PDF — malware analysis report

Static analysis result for SHA-256 c71b7d3df3399ab9…

MALICIOUS

PDF

94.9 KB Created: 2021-07-02 08:15:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 5277cb3200330dc9dc0dd91d157d4bda SHA-1: b8b760a4aec9a086c4670585d199541e2892b8ce SHA-256: c71b7d3df3399ab97a29d24e7995d9c6396c4fc303ae28915fcaa25a412c8624
156 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple external websites, some hosted on compromised WordPress installations. The presence of numerous URLs suggests an attempt to distribute malicious content or conduct phishing operations.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9936

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://philabc.ru/uplcv?utm_term=check+indexof+in+javascript
    • http://mjsolankifoundation.com/fck/imagesfile/girux.pdf
    • https://www.quatainvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16076a414c4bfc---raxazezatoloforovuvubaj.pdf
    • https://noukos.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160a3afb75ad75---dugarujelusodigaxivopika.pdf
    • https://sakitonus.ru/wp-content/plugins/super-forms/uploads/php/files/e2b82be4b3c97222213ca904e96968d0/78139401142.pdf
    • https://aljazeerahpetroleum.ae/userfiles/files/27490527437.pdf
    • http://la-roofers.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160a142de01279---93239366117.pdf
    • http://www.ddd-iasi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16089ff8e7e935---gorodebavafifu.pdf
    • https://birudongker.com/contents//files/33659797299.pdf
    • https://stefandes.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aa0e1112767---6190743715.pdf
    • https://aquaticlandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a7caf6276b6---69267938970.pdf
    • http://chicagohalo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607bfa49db8f7---6985097664.pdf
    • https://hmjrgoldhockey.org/wp-content/plugins/super-forms/uploads/php/files/73304f79ff56b32af54c1b349fc7ab5e/66242151980.pdf
    • https://renebeumer.nl/userfiles/file/12579586785.pdf
    • https://manuscripthandler.com/userfiles/file/pudirutenevedajutanobur.pdf
    • http://www.belladermeestetica.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a06de9b2ce6---2356717107.pdf
    • http://braintradingbcn.com/wp-content/plugins/super-forms/uploads/php/files/ac5f4de4529eed431485b661b772d9e5/jurud.pdf
    • http://www.johnknox.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160b7f22ecf026---divafajigitimazekibi.pdf
    • https://qboardapp.com/wp-content/plugins/super-forms/uploads/php/files/050ccffc9a3298112a55a1587d49b8b0/tujakiwiwujadoxejof.pdf
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/160b9da1c92bd6---30322448237.pdf
    • http://usaoxin.com/userfiles/2021-5/file/palodafulufu.pdf
    • http://www.akutrans.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a00a3bf0042---28244271813.pdf
    • https://iguanapools.com.au/wp-content/plugins/super-forms/uploads/php/files/331sev9ugvlaqngj78apea6nn6/jumevitagawusetitozo.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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f81a.bin
9e33fbdffefd4f83188e682a137182545928569734ab6aa5ddc29fe9fb14bf7b
pdf-font-stream PDF embedded font (sfnt) at offset 0xF81A 16372 bytes
font_01_sfnt_off00010e7c.bin
fdb814998f36ac01c691a7bd3329e5cab07090a710c6dbf4fd21e7a7797c86de
pdf-font-stream PDF embedded font (sfnt) at offset 0x10E7C 11092 bytes
font_02_sfnt_off0001285c.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1285C 16792 bytes
font_03_sfnt_off0001406e.bin
5ce09b1d3dd268d5747c3f0b2e40089bffffe3629d19781a91a0ed79cb23c435
pdf-font-stream PDF embedded font (sfnt) at offset 0x1406E 17468 bytes