Malicious PDF — malware analysis report

Static analysis result for SHA-256 4e05fcb30e8f831e…

MALICIOUS

PDF

83.5 KB Created: 2021-08-26 08:24:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 3d7581bd435ced8a4e1625efe5ecd95f SHA-1: eb5042e2e195d350a5034947deb2c392c7e19883 SHA-256: 4e05fcb30e8f831eed6d6d7d262cd8d35d6eaee4aa25cdc88a3cd61150d16f1a
156 Risk Score

Malware Insights

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

The sample is a PDF file identified as malicious by ClamAV and an ML classifier. It contains numerous embedded URLs pointing to compromised CMS uploads and disposable hosting, suggesting a link farm designed to redirect users to potentially malicious sites. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicates a deliberate attempt to obscure the true destination by using many distinct, low-reputation hosts.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 https://chcial.ru/uplcv?utm_term=removing+red+wine+from+sofa
    • https://tempatpasang.com/contents//files/bixugivu.pdf
    • http://steps4cancer.org/clients/a/a7/a78c374070a178914b502abaf3db82b8/File/lomijanunesixatotavu.pdf
    • https://martensmgt.com/business_school/uploads/file/warezu.pdf
    • https://glosunspa.com/wp-content/plugins/formcraft/file-upload/server/content/files/1611e448a93760---videtakolugalixurebuvuwu.pdf
    • http://akinmedikal.com/uploads/file/97654958383.pdf
    • https://tecnicadovolante.com/images/file/xepatiletemetovozeteka.pdf
    • https://segurosjdd.com/wp-content/plugins/super-forms/uploads/php/files/o97tlhfoqe9l03le9oqt94lf20/sivolilubawefaxafopupema.pdf
    • https://bestmiamiturf.com/wp-content/plugins/super-forms/uploads/php/files/427097ea58f1a89d6dee1b1eb89896d0/jibolotef.pdf
    • http://tdvvietnam.vn/webroot/img/files/85138816483.pdf
    • https://maloneslandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c526e4110d7---73862151142.pdf
    • http://www.absolutecateringla.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608453e4af3c1---78535933140.pdf
    • https://gotamsui.com/ck_imgs/files/23614542114.pdf
    • http://steelfurniturecn.com/d/files/5336904000.pdf
    • http://hurtglass.pl/upload/file/4130422687.pdf
    • https://www.kbstephens.com/wp-content/plugins/super-forms/uploads/php/files/3b0473d9b01db510ade0fe25cb8d508f/malofelaroxepatenaki.pdf
    • https://robotics-institute.com/wp-content/plugins/super-forms/uploads/php/files/b83o4f1q4m9vhoju2gjsvtuk4h/jukodovajegu.pdf
    • http://aelma.com/sites/default/userfiles/file/59269590563.pdf
    • https://laxmigrouppune.com/wp-content/plugins/super-forms/uploads/php/files/224badac21e6fb95f76291556444aeb5/makuwekuvuketuxenezikijot.pdf
    • http://sosnovgeo.ru/userfiles/file/dekurejalolazuzubaj.pdf
    • http://www.ncstarim.com.tr/wp-content/plugins/super-forms/uploads/php/files/60fjqqtcq8tu9jh6k4gnmub1l4/16141506144.pdf
    • http://falegnameriacastiglione.it/userfiles/files/7782373961.pdf
    • http://files.ibiza-ferien.de/file/mojetiri.pdf
    • https://eminencesolutions.in/resources/userfiles/file/77557540361.pdf
    • http://ventima.ru/userfiles/file/99123388254.pdf
    • http://becro-plast.hr/wp-content/plugins/formcraft/file-upload/server/content/files/160e6c34c980ff---zijetapo.pdf
    • 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_off0000e1fa.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE1FA 16792 bytes
font_01_sfnt_off0000fa11.bin
6ffa922017f31c7d895662f5a039a32c3ccdc22a015c3d88d45a72019a01c1d8
pdf-font-stream PDF embedded font (sfnt) at offset 0xFA11 10752 bytes
font_02_sfnt_off0001129c.bin
f8c32c69c7cf526e0a9060aafc8c3d10f56df46b3b8dec31cb4d6e48b4c85239
pdf-font-stream PDF embedded font (sfnt) at offset 0x1129C 16980 bytes