Malicious PDF — malware analysis report

Static analysis result for SHA-256 8a21065bedb04258…

MALICIOUS

PDF

83.3 KB Created: 2021-08-02 17:12:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 8073a7e64098cb5deae0a390db37650b SHA-1: 5977395a423f54462d553076c78d1c904d7f4483 SHA-256: 8a21065bedb0425858479edb14030df54c95f6fbeee1a7af949873fb76d756ee
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites and disposable domains, indicating a link farm or phishing lure. The ML classifier and ClamAV detection strongly suggest malicious intent. The primary attack pattern involves directing users to external, potentially malicious, content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

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://hodinovysoused.cz/upload/file/muzimewonizip.pdf
    • https://pankalconstructora.com/wp-content/plugins/formcraft/file-upload/server/content/files/160791aa63e91e---65311084545.pdf
    • http://cdseoulps.com/uploadfile/fckeditor/file/fodamatusajixuvubadu.pdf
    • http://yorktownhs1987.com/clients/57482/File/56740201850.pdf
    • https://cyberbirddog.com/userfiles/files/fifabufijamejenuwedadi.pdf
    • http://kondicionery-domodedovo.ru/upload_picture/file/nixevefuve.pdf
    • https://omomediacion.com/wp-content/plugins/super-forms/uploads/php/files/41a8f6d0ccb4bc0b5cc8254d6d8f3fb2/xofimumogex.pdf
    • http://intechsol.kz/wp-content/plugins/formcraft/file-upload/server/content/files/160c140a5e66f8---lepaban.pdf
    • http://charontrade.hu/data/file/tumuzineke.pdf
    • https://www.elementstraining.co.uk/wp-content/plugins/super-forms/uploads/php/files/t4130f2uenrvoufmcbq3o2q773/66966555428.pdf
    • https://arhometutor.com/userfiles/file/dobibedubemodefetame.pdf
    • http://dailitara.lt/bites/uploads/file/muzokisasogego.pdf
    • https://nowbali.co.id/wp-content/plugins/formcraft/file-upload/server/content/files/160a90cb9817f0---64314883.pdf
    • http://abwingssuffolk1.com/uploads/files/32373378132.pdf
    • https://leganordavigliana.it/uploads/file/8125629974.pdf
    • http://boeschfamilytravels.com/clients/43210/File/29564072560.pdf
    • https://gz-topstar.com/wp-content/plugins/super-forms/uploads/php/files/67e5187581364d2fa42885b12bb8f471/14346618363.pdf
    • http://worksafeorg.com/wp-content/plugins/super-forms/uploads/php/files/75cla8fmfkp9s0k80ispk4d3d3/35991927402.pdf
    • https://aannemingsbedrijfbarthulsbosch.nl/userfiles/file/54681224317.pdf
    • https://facades-metal.ch/ckfinder/userfiles/files/manigopirojejosubilage.pdf
    • https://makemycake.gr/wp-content/plugins/super-forms/uploads/php/files/rh3la3ec1hgi83nj2m91499453/zevigejepidukabos.pdf
    • https://rhagro.com.mx/wp-content/plugins/super-forms/uploads/php/files/57dfb68fa7dd6d523c06d009b51d8d46/11366292408.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=algebraic+fractions+gcse+worksheet
    • 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_off0000e05e.bin
3ffa31769c8df9ba998766f937e0666fc9d3f67fe5129f7602d5e4a7129a5e65
pdf-font-stream PDF embedded font (sfnt) at offset 0xE05E 17140 bytes
font_01_sfnt_off00010d49.bin
efe0aef8d21a9ed6d52bd3de0b98a776aa0e43660d0e86c65bd9149a2288fc7d
pdf-font-stream PDF embedded font (sfnt) at offset 0x10D49 10912 bytes
font_02_sfnt_off0001269a.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1269A 16792 bytes