Malicious PDF — malware analysis report

Static analysis result for SHA-256 4d18c6dc8f082c4b…

MALICIOUS

PDF

87.3 KB Created: 2021-06-26 12:35:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c12dff4fa134aefeb2f2e2d00479e229 SHA-1: dad22bd9def3dfb704e4e489e5968a9ab20f7ce1 SHA-256: 4d18c6dc8f082c4bb74d3ffca8596fd37b7790f48542b1258b2df1c859551d3c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The document functions as a link farm, containing numerous URLs pointing to compromised WordPress sites and disposable hosting. These links likely serve as lures for phishing attacks or to distribute further malware. No scripts were extracted, but the PDF structure itself is used to host and present these malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://nomylo.ru/uplcv?utm_term=thank+you+email+for+promotion
    • http://thanhlamresort.vn/wp-content/plugins/formcraft/file-upload/server/content/files/160ab43a1011e1---wowipit.pdf
    • https://3dreamstudios.com/wp-content/plugins/super-forms/uploads/php/files/f7243b534f038a936451446f3ca1db20/jazemaboromunofuzotavule.pdf
    • http://diversecityuk.com/userfiles/file/39887262305.pdf
    • http://nct-vn.com/userfiles/file/79694293764.pdf
    • http://rurisnet.org/images/file/354617589.pdf
    • https://jdrum-music.com/uploads/ckfiles/files/98488425709.pdf
    • https://luathoanghuy.com/uploads/files/jozurifagibuzeg.pdf
    • https://www.marthatrotts.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160c7427e07c45---88968387623.pdf
    • http://admio.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160a11cf37f611---nevuboze.pdf
    • https://armagedonspedycja.pl/files/file/14148566539.pdf
    • https://www.chinacimctrailer.com/wp-content/plugins/super-forms/uploads/php/files/dc098a2fbd966c090b60bd4648de10d0/56531383083.pdf
    • https://brokenspoke.com/wp-content/plugins/super-forms/uploads/php/files/cc67432593182074a6577b1f097f8cf6/4401975577.pdf
    • http://interel-rus.ru/test/sites/default/files/file/31673255653.pdf
    • http://wypelnienia.kratex.pl/wp-content/plugins/super-forms/uploads/php/files/1bfbec6ca97041fb1e65946ee050417b/zinorefekerumirim.pdf
    • https://ankaratemizlikcim.com/depo/sayfaresim/file/muzotako.pdf
    • http://www.johnknox.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160b433bb04329---fogowofote.pdf
    • https://unicornproduction.gr/wp-content/plugins/super-forms/uploads/php/files/3137f6b8f9b5c84748345d2ab7afba89/79207248877.pdf
    • http://maroba-zirndorf.de/file/rogovanuno.pdf
    • http://irmascaritasdejesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/160926c96cc6d0---44795100753.pdf
    • http://montaze.org/democms/userfiles/file/10964948807.pdf
    • http://ceomit.com/fckupload/file/tusemujasojojufalif.pdf
    • http://j-club.eu/userfiles/file/4547976548.pdf
    • https://www.ergunaygoren.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607aaac33915a---30127548306.pdf
    • https://avantkart.com/wp-content/plugins/super-forms/uploads/php/files/qljn6qn8v3du4bnkeq83rjq756/92248055858.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_off0000f2ff.bin
3aef93b84740c3428a5d4145e61fa7ff7339bfb2aa4b0f9ae8d0099ce6f771e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF2FF 16988 bytes
font_01_sfnt_off00011f6f.bin
d7f4877327f6c30634a4749f015845b0d2dd4c85791168b06576ecfcf364bc0a
pdf-font-stream PDF embedded font (sfnt) at offset 0x11F6F 10724 bytes
font_02_sfnt_off000137d8.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x137D8 16792 bytes