Malicious PDF — malware analysis report

Static analysis result for SHA-256 28d1a0802433d9b1…

MALICIOUS

PDF

82.1 KB Created: 2021-06-20 10:44:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-07
MD5: 1400bb79894122983dd10b0077a5d7d0 SHA-1: 80c5996bfe8d5a14740d3d84deb0b787e8386854 SHA-256: 28d1a0802433d9b1532e7ad26c50ce9ed5e422a8ebd6d223956e1a8030609214
164 Risk Score

Malware Insights

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

The PDF contains multiple links to external websites, many of which are hosted on compromised CMS platforms, suggesting a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely a phishing lure for downloading unwanted software or malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://masterok-kovka.ru/wp-content/plugins/super-forms/uploads/php/files/d1c6d8c4ae401333e3ef6e239344c922/77022318295.pdf In PDF document text
    • https://hophamthaibinh.com/upload/files/86225905039.pdfIn PDF document text
    • http://www.gainerwindows.ca/wp-content/plugins/super-forms/uploads/php/files/3kbo2n3n6pof6967f1gllg83l2/85429135738.pdfIn PDF document text
    • https://mamproducciones.es/wp-content/plugins/formcraft/file-upload/server/content/files/1608e526e19a14---lagexalaf.pdfIn PDF document text
    • http://www.psstrecno.sk/wp-content/plugins/formcraft/file-upload/server/content/files/160b806604a7b3---26212901699.pdfIn PDF document text
    • https://forcechicago.com/wp-content/plugins/super-forms/uploads/php/files/fb5098e3769e56b9bb89df5695fbf8b1/xezetaregifitax.pdfIn PDF document text
    • http://quickfix-poland.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a70bca0ad28---69146181216.pdfIn PDF document text
    • https://www.hdontheroadnapoli.it/wp-content/plugins/formcraft/file-upload/server/content/files/160718fdcee1d8---56725784840.pdfIn PDF document text
    • https://www.ltgpartners.com/wp-content/plugins/super-forms/uploads/php/files/3f1f5d7362dbe288125b48ae5a98209f/90234945796.pdfIn PDF document text
    • https://condominiovillage.com/userfiles/file/43262644779.pdfIn PDF document text
    • https://webgirls-studio.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a8443323033---mozimakijuworubedez.pdfIn PDF document text
    • http://bpabv.nl/uploadfiles/file/24834782922.pdfIn PDF document text
    • http://astro2sphere.com/admin/images/file/43027194126.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=download+gta+5+android+obb+filePDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ec0e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC0E 5252 bytes
SHA-256: c220e4b43d32d15e8c7741b23cc02e85eab3bd1cdd1f6f794740f628d078a9ee
font_01_sfnt_off0000fe1b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE1B 11076 bytes
SHA-256: 48b206d711c6f3473bcf190033fa08f7a7fbc9c115dbff6e11837ca3b89189a0
font_02_sfnt_off0001240e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1240E 16756 bytes
SHA-256: 66ebc0a0ad91e65a10baeb16446991f67cccedd9ebfb903d71229f49e92537dd