Malicious PDF — malware analysis report

Static analysis result for SHA-256 0a7e31ce62a2d8e6…

MALICIOUS

PDF

83.3 KB Created: 2021-08-16 22:27:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: ea6fa135dfaf53880743b0c0e6893795 SHA-1: d72afa30b9512580587f4f161b516fe2b2476390 SHA-256: 0a7e31ce62a2d8e6d7bc81808e35a2442c652f775590f302f195e1d538a0b9da
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file detected as malicious by ClamAV and an ML classifier. It contains numerous links pointing to compromised CMS upload storage and disposable hosting, indicating a link farm designed for phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and URL patterns suggest it's intended to lure users to malicious sites, likely as a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9983

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://nsck-cykelmotion.dk/userfiles/file/sidorumuli.pdf
    • http://www.jindatunnel.com/up_files/file/jasibimin.pdf
    • http://www.fullmooneye.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072b8815092c---ramitebaxizibinagabezere.pdf
    • http://kibbkw.com/uploads/files/71890116067.pdf
    • https://www.idahomedia.com/wp-content/plugins/super-forms/uploads/php/files/c79b93dd0382eed190e64b61ff299b1c/49011565502.pdf
    • http://xn--9w3b11kh5l.com/ckupload/files/bikomigejuzeb.pdf
    • https://aldapa.eus/files/galeria/files/luwut.pdf
    • http://gistfamilyreunion.com/clients/8/8c/8cbf0a40baaab9dd4734ff2cdbb1e120/File/bemiloridavimomisosax.pdf
    • https://canionglobal.com/FCKeditor/file/48577060887.pdf
    • https://aprilboya.com/userfiles/file/bideli.pdf
    • http://www.maoles.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075cffe231ff---dufigabesobuni.pdf
    • https://ascinfratech.com/clientprojects/trading/file/96877789197.pdf
    • https://event-connections.net/wp-content/plugins/formcraft/file-upload/server/content/files/1609abd4d5bb29---11048976294.pdf
    • http://langeline.com/ckeditor/upload/files/45643231846.pdf
    • https://twr1115.net/files/fckeditor/file/zafipafunenojurelugox.pdf
    • https://mavismanagement.com/wp-content/plugins/formcraft/file-upload/server/content/files/160dfc3552d048---47708360022.pdf
    • http://parkwestresidences.com/wp-content/plugins/formcraft/file-upload/server/content/files/160855f0805be5---mididupo.pdf
    • https://planet-pvc.com/upload/files/puremawis.pdf
    • http://buzmakov-ua.ru/admin/ckfinder/userfiles/files/51239537462.pdf
    • https://propbrains.com/wp-content/plugins/super-forms/uploads/php/files/jc93kjhbs0np984tthmrp1chm3/72283451097.pdf
    • https://completecollegestrategies.com/wp-content/plugins/super-forms/uploads/php/files/2f76e4e77ec7bb16ea8ab4507aa9844d/31088856485.pdf
    • http://franzoesischebulldoggen.eu/userfiles/file/nigiroz.pdf
    • https://webhostmurah.com/wp-content/plugins/formcraft/file-upload/server/content/files/160fdfe561d890---sekol.pdf
    • http://english-island.pl/wp-content/plugins/super-forms/uploads/php/files/8u7v86dfnv6v4a6ucck2t0u401/6156221928.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=which+statement+best+summarizes+the+first+paragraph+of+the+declaration+of+independence
    • https://sharpspringwww.kinsta.cloud/wp-content/plugins/super-forms/uploads/php/files/ff67fcd473bdfea4d0cb38fb3388f9eb/fefilumilivuzam.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_off0000e17d.bin
a0d633f4196a3b2978c3fecc4084222e4d5ee1c0fec7dfcd1f23242edd65f120
pdf-font-stream PDF embedded font (sfnt) at offset 0xE17D 11360 bytes
font_01_sfnt_off0000fbab.bin
054bcd5ed1ba6046cf44dc73c669c5aae244ac9447f5c5e0b28335cc70060057
pdf-font-stream PDF embedded font (sfnt) at offset 0xFBAB 16160 bytes
font_02_sfnt_off00012535.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12535 16792 bytes