Malicious PDF — malware analysis report

Static analysis result for SHA-256 8d04f8f5e4b6d104…

MALICIOUS

PDF

86.9 KB Created: 2021-07-04 04:05:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4cfd9eadf1ef02b4112d125f43c88d77 SHA-1: 6d6d321d95c624549c1b91136d0797e31cf44725 SHA-256: 8d04f8f5e4b6d1046bf10e88095a6ce6c7417806da2a885b6ae3edd680f0c4b9
156 Risk Score

Malware Insights

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

The PDF contains numerous external links, many pointing to compromised CMS upload directories, suggesting a phishing or malware distribution scheme. The ML classifier and ClamAV detection strongly indicate malicious intent. The document body is unreadable, but the heuristic firings and URL analysis confirm the link farm attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

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://inwebjor.ru/uplcv?utm_term=different+types+of+twists
    • http://bakkervoorwinde.nl/app/webroot/files/ckeditor_files/files/gazuvu.pdf
    • https://olmitek.by/wp-content/plugins/super-forms/uploads/php/files/bodkplnu6o24uqrl2vc3388b33/ponidifuwosave.pdf
    • http://asu.com.vn/wp-content/plugins/super-forms/uploads/php/files/s5b0mbvsnrg1clkbrtnb2v7e11/68742658997.pdf
    • https://414movement.com/wp-content/plugins/super-forms/uploads/php/files/2454f3da08fa874f0cc317cb0ad35794/97682469532.pdf
    • http://dobrasekacka.cz/userfiles/file/pononivupizabelakakudi.pdf
    • http://msinziniering.com/userfiles/file/6915516421.pdf
    • https://primax.fr/wp-content/plugins/super-forms/uploads/php/files/u0vpb7o0r62020mu90eji2c376/zupumom.pdf
    • https://www.quatainvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160caa7794577f---sapatetakofeten.pdf
    • http://www.catalogodecineargentino.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e7bdbd0e91---21868518770.pdf
    • https://www.advids.co/wp-content/plugins/formcraft/file-upload/server/content/files/160ad4f2d5415a---90729311942.pdf
    • http://tz5168.com/uploadfile/image/2021/05/22/file/20210522_220925_109.pdf
    • http://ztkammer.at/uploads/file/febixilafipakuzolakeri.pdf
    • http://www.hollyskauaicondo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b2918b2076---48123133811.pdf
    • http://conwaychristian.org/wp-content/plugins/formcraft/file-upload/server/content/files/160996e091e10b---lugulafovokolemuke.pdf
    • https://yuss.it/file/parepima.pdf
    • http://www.northeastmarquees.com/wp-content/plugins/super-forms/uploads/php/files/a7f918090fc16e7ec8f3ecf9968dd307/78619054343.pdf
    • http://sosnovgeo.ru/userfiles/file/7288809070.pdf
    • https://1sis.com/wp-content/plugins/formcraft/file-upload/server/content/files/160853633c1c02---53057579528.pdf
    • http://brandnewgoods.net/userfiles/file/50343700717.pdf
    • https://arizonalightingsales.com/wp-content/plugins/super-forms/uploads/php/files/eb815c5882506cf0549475896c517182/xinuzegiwisomegedumonuje.pdf
    • http://taiwanglassgroup.cn/userfiles/file/83735873038.pdf
    • http://driver-jazda.pl/upload/file/55461898356.pdf
    • http://www.k-24.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ce8cf86ebe---miketadokuvip.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_off0000f0c0.bin
6f43d4206a9a5d27bd0051a1d4c15e233ad6d7da666254095598d4b7bf697a03
pdf-font-stream PDF embedded font (sfnt) at offset 0xF0C0 17132 bytes
font_01_sfnt_off00011d5e.bin
010dbff45944a6f8a4a894c8899dd42437f78169fc2aa6ac641def2ee0aaba3b
pdf-font-stream PDF embedded font (sfnt) at offset 0x11D5E 10344 bytes
font_02_sfnt_off000134f0.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x134F0 16792 bytes