Malicious PDF — malware analysis report

Static analysis result for SHA-256 8bf42dc903371f21…

MALICIOUS

PDF

94.1 KB Created: 2021-06-28 02:15:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 119dbbf0b06655c649768a589d4337dc SHA-1: b41c42ca2c2f467fc96cc62a018e47f68b167160 SHA-256: 8bf42dc903371f215ad24c740288337fac51721c56b56b9d0b5af4b872c32936
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The file was detected by ClamAV as Pdf.Phishing.Trojan and an ML classifier flagged it with high confidence. It contains numerous links pointing to compromised WordPress upload storage and other disposable hosting, indicating a link farm designed to redirect users. The PDF structure itself is not directly malicious but serves as a lure to these external, compromised sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://kamber.dk/wp-content/plugins/super-forms/uploads/php/files/c644808e8873d6103448c3e3c14cc315/27803546913.pdf
    • https://bykevin.com/wp-content/plugins/super-forms/uploads/php/files/d7c682c7dfeb342c8daed1d436538832/somad.pdf
    • https://guapa2.com/admin/fck/file/75642455513.pdf
    • https://action-roofing.com/wp-content/plugins/super-forms/uploads/php/files/1968c8f99f92721dec2cf501b9cebbee/19431431226.pdf
    • http://www.empresasdelimpeza.info/wp-content/plugins/formcraft/file-upload/server/content/files/160c6abc12390e---29904061530.pdf
    • http://www.combatsim.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1609b497839600---10970010855.pdf
    • http://copelandreunionla.com/clients/6/66/66f6f3de7053633686652f51c4c00696/File/danoxipoj.pdf
    • http://gennarimaq.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608509540b92b---27761312917.pdf
    • http://gpszone.hu/upload/userfiles/file/bawigalidago.pdf
    • https://trucraftsmanship.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cfd0357a1af---43038098929.pdf
    • http://akbmodel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bb700b3634e---sobez.pdf
    • http://kardelendalgicpompa.com/uploadfiles/file/5195798712.pdf
    • http://www.melodypods.com/wp-content/plugins/formcraft/file-upload/server/content/files/16099eff2e3395---lolajevomasipototep.pdf
    • https://www.engltg.com/wp-content/plugins/super-forms/uploads/php/files/a94732486190973d222700f575b640e4/98654687486.pdf
    • http://thanhlamresort.vn/wp-content/plugins/formcraft/file-upload/server/content/files/16089bd61c6abd---mexuzeb.pdf
    • http://novichiha.ru/pic/file/gorulovasifi.pdf
    • http://cnokorea.com/userfiles/file/3137529174.pdf
    • https://www.idromeccanicasrl.com/idromeccanicasrl.com/wp-content/plugins/super-forms/uploads/php/files/de3d5bdbb2a9a87f25c853336f0659c2/wafisirumu.pdf
    • https://asaptransfers.co.uk/wp-content/plugins/super-forms/uploads/php/files/nl9mjbbqpc4ldshl5h6d47nft7/terabekapazobokibunoro.pdf
    • http://pampa.be/uploads/userfiles/files/kifisojanep.pdf
    • https://spaslask.pl/wp-content/plugins/super-forms/uploads/php/files/gli5sud1jcvfdnmq9k1c7ih4av/37974315176.pdf
    • http://www.scmphotography.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1606d5c9688836---wulojogumekamebirususimi.pdf
    • https://dazzlin.co.uk/wp-content/plugins/super-forms/uploads/php/files/6cd7a8eabedda1cdbe6c93b7fe08bf98/buxuxisaburapig.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=fix+gyroscope+android
    • 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_off00010b48.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10B48 16792 bytes
font_01_sfnt_off0001235f.bin
4d1763f69172a53da7cbc4411c32a668dd694011a13a0bcd1cba0e531985c92c
pdf-font-stream PDF embedded font (sfnt) at offset 0x1235F 10740 bytes
font_02_sfnt_off00013bf4.bin
fed16f62d8c3dfeaedb0f83bece6002e874d897315c0ac48584c5fc637de4de4
pdf-font-stream PDF embedded font (sfnt) at offset 0x13BF4 17792 bytes