Malicious PDF — malware analysis report

Static analysis result for SHA-256 2c4ca3c05db45b50…

MALICIOUS

PDF

84.8 KB Created: 2021-08-21 05:17:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 8beb46ca4dfa8a313cf298956635c6dd SHA-1: 9d71ed8ba883d83cf2447d9ae06a339f7801d7e3 SHA-256: 2c4ca3c05db45b5072eef4994d463983896a2c8b6665603431dc6c465d6310df
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to various domains, many of which are hosted on compromised CMS platforms or appear to be disposable. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The document body is heavily obfuscated and unreadable, providing no direct clues to its purpose beyond the heuristic findings.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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 http://usmleworkout.com/files/file/vuwejivevazapixo.pdf
    • http://primebrokeragetx.com/ckfinder/userfiles/files/bixuvatagezesoxuvalovi.pdf
    • http://bannails.com/fckeditor_userfiles/file/48862935660.pdf
    • http://cobmedia.hu/include/rarebuno.pdf
    • https://alismobile.co.uk/wp-content/plugins/super-forms/uploads/php/files/697bb222017b901e0d795d789e40dfcc/fuxiwinev.pdf
    • http://elonsummerstorage.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a84bb459f05---bubirenitikovofuxexibile.pdf
    • https://selispin.com/calisma2/files/uploads/67801309840.pdf
    • https://ohcsi.com/ckfinder/userfiles/files/goroluj.pdf
    • http://xn----7sbakif2a3azdub.xn--p1ai/admin/ckfinder/userfiles/files/fudofaz.pdf
    • http://csc0512.com/userfiles/file/20210629211957_mcp70w.pdf
    • https://www.capitalroofingct.com/wp-content/plugins/formcraft/file-upload/server/content/files/1611fa1c560810---rerefutubewetuxad.pdf
    • https://lightspec.ca/wp-content/plugins/super-forms/uploads/php/files/cd3870289721809d527ce4d8ac843105/68350081200.pdf
    • https://tractorpulling-emmeloord.nl/upload/file/tasamapepekefudebenaseni.pdf
    • http://structurecreative.com/wp-content/plugins/formcraft/file-upload/server/content/files/1610ccb90be915---63724962419.pdf
    • http://www.icodar.com/wp-content/plugins/formcraft/file-upload/server/content/files/16099b40da91a0---sukevimewonis.pdf
    • https://teenvolunteerdallas.org/wp-content/plugins/super-forms/uploads/php/files/3fe3a4ae6dc71d5c1706203e7de87927/wiwofodose.pdf
    • https://ivanamihic.com//files/8098013044.pdf
    • https://invest.pl/userfiles/file/37356171027.pdf
    • https://www.tifdip.com/wp-content/plugins/formcraft/file-upload/server/content/files/160870dc761a82---ritupigiwevamuto.pdf
    • https://amirep.com/wp-content/plugins/super-forms/uploads/php/files/e5d846374a82b834a24c2f79ba30636e/gokogetoravixi.pdf
    • http://ophtalmic-overnight.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1606f047340c7f---vuwedabosemiragisu.pdf
    • http://mintaialuminum.com/d/files/36715145494.pdf
    • http://careerhack.net/wp-content/plugins/formcraft/file-upload/server/content/files/16087c47b7652b---kuburidokikapabaroguv.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3CAf4wW3hvY/uplcv?utm_term=chapter+16+the+digestive+system+packet+answers
    • 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_off0000e87a.bin
14050d383347465312ad0d5b9674a21bd4a3abfc77c0846003ba585ff72826d4
pdf-font-stream PDF embedded font (sfnt) at offset 0xE87A 16076 bytes
font_01_sfnt_off000111df.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x111DF 16792 bytes
font_02_sfnt_off000129f6.bin
ab0adbb75b53d833d95fec47369b5410c58111321be41e483d75d9f9837efdad
pdf-font-stream PDF embedded font (sfnt) at offset 0x129F6 11404 bytes