Malicious PDF — malware analysis report

Static analysis result for SHA-256 ba9ab4b4b50bcf79…

MALICIOUS

PDF

70.7 KB Created: 2021-07-20 09:59:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: f190beb404eabd141b5df15ce629cb67 SHA-1: 627f5405b5a2ef606c6da16af8c970abea048a89 SHA-256: ba9ab4b4b50bcf79d84581f8be8c805122438d3b3ce82502bdabf60df1e68b01
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as a phishing trojan. It functions as a link farm, directing users to multiple compromised WordPress sites and disposable domains, likely for phishing or malware distribution. No scripts were extracted, but the presence of numerous external URIs and the 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic strongly indicate a malicious intent to redirect users.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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 http://anhuifan.com/upload_fck/file/2021-5-17/20210517115635801464.pdf
    • http://www.myhhsi.com/wp-content/plugins/super-forms/uploads/php/files/1ba692dd94f1276fe983a0689f3f5a39/68148498915.pdf
    • http://nhs1980alumni.com/clients/878257/File/zufomeguxasasugan.pdf
    • https://spa-salon.ru/ckfinder/userfiles/files/7752814828.pdf
    • https://kvgrup.com.ua/wp-content/plugins/formcraft/file-upload/server/content/files/1608668fedb961---28553279267.pdf
    • http://provia-events.de/pics/fotos/1/file/jotewegivoj.pdf
    • https://veritiesinstitute.com/wp-content/plugins/super-forms/uploads/php/files/0322d5a0486b1b8f4057895f1df0ab93/gizonudawakorolevupaxox.pdf
    • https://agermag.ro/mm/file/zatunogaduruxodun.pdf
    • http://mextro.de/upload/files/sugejod.pdf
    • http://zekidilektekstil.com/images_upload/files/1985005470.pdf
    • https://murtenhof.ch/userfiles/files/zubidipotawajugenimujoke.pdf
    • https://textosolutionslinguistiques.ca/upload/editor/file/96509490140.pdf
    • http://hakkabrothers.com/userfiles/file///34025679340.pdf
    • https://www.pfgpartners.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160be8358a459e---3060606111.pdf
    • https://www.qlsny.com/wp-content/plugins/super-forms/uploads/php/files/212f12da89acbece0150de9f46e0c297/faxeg.pdf
    • https://travelselection.us/wp-content/plugins/formcraft/file-upload/server/content/files/160c2b07ccefc3---18796345667.pdf
    • http://fincasotilloviejo.es/files/sotillo/_repo/file/7387198898.pdf
    • http://cerrutistudio.eu/userfiles/files/kevagujelaxugijakorubenob.pdf
    • https://www.web2business.pt/wp-content/plugins/formcraft/file-upload/server/content/files/1607c895b7cc33---57565914766.pdf
    • https://www.idromeccanicasrl.com/idromeccanicasrl.com/wp-content/plugins/super-forms/uploads/php/files/087b297908d13b9b300af29dd49bfb88/57343881790.pdf
    • http://vipavtoufa.ru/wp-content/plugins/super-forms/uploads/php/files/4aa6d71b0d56521b3dc25f8a9fc099eb/68216028469.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=brian+cook+md
    • 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_off0000b642.bin
75aedaea2f0ed5eaf5678205922125c2623bbd210d1dbd9b53fd03c289896f22
pdf-font-stream PDF embedded font (sfnt) at offset 0xB642 10232 bytes
font_01_sfnt_off0000cd31.bin
7f46fba588472eeed0c871f35fd89c2f5f2dc804c7571385ddaea7e7158f708f
pdf-font-stream PDF embedded font (sfnt) at offset 0xCD31 15916 bytes
font_02_sfnt_off0000f61b.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF61B 16792 bytes