Malicious PDF — malware analysis report

Static analysis result for SHA-256 c4495405574e5f9b…

MALICIOUS

PDF

82.8 KB Created: 2021-06-25 12:46:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 082e41a6e8be97f756883ec7785d0a8a SHA-1: 2409fe1a0e3ef7a971afa45d77eea7852fb9d76c SHA-256: c4495405574e5f9b84da91d65b10cd172cb3cc39b6084a4ddf99d89c3f179e8b
156 Risk Score

Malware Insights

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

This PDF was flagged by multiple heuristics and an ML classifier as malicious, with ClamAV identifying it as a phishing trojan. It contains a link farm pointing to compromised WordPress upload directories, suggesting an attempt to redirect users to malicious content. The document body is heavily obfuscated, preventing a clear understanding of its specific lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://www.loicadesacavem.pt/wp-content/plugins/formcraft/file-upload/server/content/files/16095e32d5cfcb---90238883417.pdf In PDF document text
    • https://mytekas.com/UserFiles/file/59209995087.pdfIn PDF document text
    • https://dovolena-jiznicechy.cz/uploads/14278405855.pdfIn PDF document text
    • https://monacollection.ua/wp-content/plugins/super-forms/uploads/php/files/6e8e1ba9121a8a6cd52cdf9d525c554a/pafepunidiwolezonufubuf.pdfIn PDF document text
    • http://www.virtualaid.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160789b000315a---rapepakejedilaferatuw.pdfIn PDF document text
    • https://www.qbuildsoftware.com/wp-content/plugins/super-forms/uploads/php/files/14008a13ba8beaf412e973462d0cf988/gomiz.pdfIn PDF document text
    • https://cashmeredreams.com/wp-content/plugins/super-forms/uploads/php/files/350df7d9aa95d53a491e8104ecb2bf67/71004952918.pdfIn PDF document text
    • http://indovinandoilmondo.it/themes/userfiles//files/70265702379.pdfIn PDF document text
    • https://smoothnomad.com/wp-content/plugins/super-forms/uploads/php/files/al0en8g7mcuhrufilttp9k8cfs/jiposuziguvojemo.pdfIn PDF document text
    • https://nowbali.co.id/wp-content/plugins/formcraft/file-upload/server/content/files/1606fdd6b7a123---67768161880.pdfIn PDF document text
    • http://fusheng-vietnam.vn/admin/webroot/upload/image/files/91486051113.pdfIn PDF document text
    • http://www.blackhillsdancecentre.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b511f3b40be---42953766773.pdfIn PDF document text
    • https://ecomassage.pt/wp-content/plugins/super-forms/uploads/php/files/i8h5v8sj5frp1vvqakv4jo6dim/novibino.pdfIn PDF document text
    • http://osullivanspressurewashing.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609cde881b759---86517100681.pdfIn PDF document text
    • http://traditionsradio.com/wp-content/plugins/super-forms/uploads/php/files/3pkl0v40bbr3iove7kb2vp2qb1/rofodixijukejabupotelek.pdfIn PDF document text
    • http://hydrem.ru/images/file/81835237579.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=be+wise+like+a+snake+bible+versePDF 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://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_off0000e390.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE390 16776 bytes
SHA-256: 10dbace1791c61af2b38d4c8b16cfa617e9c6e100ec898f567bdb647a03358ba
font_01_sfnt_off00010f23.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F23 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001273a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1273A 10320 bytes
SHA-256: 5e6b25d598a97736fc585bd8cc880ffdec23297e96b1f01c17e8921c62529b78