Malicious PDF — malware analysis report

Static analysis result for SHA-256 160b3a386f37708f…

MALICIOUS

PDF

82.7 KB Created: 2021-09-02 16:47:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 612d07a57a510f445bca5086e3a19501 SHA-1: 851c19c3fafdfc126cb9b769d89a02184e0a72bd SHA-256: 160b3a386f37708f20756e781c0486bc5674f9eea04f7700897ba4025efa1720
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs that form a link farm, with many pointing to compromised WordPress sites or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. No scripts were extracted, but the link farm structure is a common tactic for initial access.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://fallsplat.se/file/maxikemivagozikijelusuwi.pdf
    • http://mediacast.vn/ckeditor/upload/files/24028159025.pdf
    • http://sciencevier.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ce2d8a1c088---sizeterosegiga.pdf
    • http://wallacewilliamsfamilyreunion.net/clients/6/66/662ca4338cd1fa41fa93b88222973dc6/File/59390996865.pdf
    • https://www.inkfactory.pk/wp-content/plugins/formcraft/file-upload/server/content/files/160be6bfb2dccf---tesutuwivuwigusubo.pdf
    • http://www.fullertherapy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609bb15288f42---julekitugukijase.pdf
    • http://www.pointcookelectrician.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160c2ea9912a49---77964704388.pdf
    • https://vinaconexmec.vn/uploads/news_file/vogisobuxazotovejuferitoj.pdf
    • http://camel-republic.com/media/userfiles/files/45867094156.pdf
    • http://etasystem.net/userfiles/files/3691595811.pdf
    • http://anhuifan.com/upload_fck/file/2021-5-10/20210510131551713653.pdf
    • https://eniedu.com/data/file/20210807054653.pdf
    • https://www.cr-sdc.org/wp-content/plugins/super-forms/uploads/php/files/81aaa29073df2984a2a04cc215d5a45d/mibejuvutareviligonil.pdf
    • http://clubsahdianagalati.ro/upload/editor/file/pusokexafit.pdf
    • https://na-nule.ru/wp-content/plugins/super-forms/uploads/php/files/ocbv1rm6607gelbb514mdv6n86/48727547668.pdf
    • http://totaleclipsenv.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b3ecc3190d9---bogikozerakuf.pdf
    • https://cristiandellavedova.com/wp-content/plugins/super-forms/uploads/php/files/g2c7u4q0l7h3upicj2bbhtke00/penabab.pdf
    • http://www.siscard.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a35545b32e9---babodegu.pdf
    • https://www.ndgai.com/wp-content/plugins/super-forms/uploads/php/files/e6i4iprou20lvtagf9938qpapf/bitabezegepuku.pdf
    • http://penoplex24.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1608695095c3a7---pasowi.pdf
    • http://gwtcs.org/Content/uploads/files/53281667413.pdf
    • http://pamatudarbai.lt/ckfinder/userfiles/files/56308356457.pdf
    • http://www.redactordecontenidos.eu/wp-content/plugins/formcraft/file-upload/server/content/files/16092280ac2374---kifekitozunapakukoz.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=property+misdescriptions+act+1991+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_off0000dd72.bin
6b521facfdfb8bd6af0674b87d664df5f1750d0474a99f25259b32410c752518
pdf-font-stream PDF embedded font (sfnt) at offset 0xDD72 11068 bytes
font_01_sfnt_off0000f751.bin
0ed89e8783a34187d7ed2e5d007b19b125bc38c520e1f4ee81cf42b42952d95b
pdf-font-stream PDF embedded font (sfnt) at offset 0xF751 17568 bytes
font_02_sfnt_off00012511.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12511 16792 bytes