Malicious PDF — malware analysis report

Static analysis result for SHA-256 36ae1a3d3ce78060…

MALICIOUS

PDF

82.0 KB Created: 2021-09-03 23:51:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 29f77a298f80145f537148c99b0a69db SHA-1: 01876b98f7f647fdf4b91f4a3f2883af8e09abbf SHA-256: 36ae1a3d3ce78060913550c705676c450e8545d54c11de64cd49fa3d70033603
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to external sites, including those hosted on compromised CMS upload storage. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution through these links. The document body is heavily obfuscated and does not provide readable content, but the heuristic firings and URL analysis are sufficient to determine the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://elskup.pl/images/assets/file/30715737012.pdf In PDF document text
    • http://churchontherockuk.org/home/churchontherock1/public_html/userfiles/files/34790584496.pdfIn PDF document text
    • http://dakmet.pl/upload/kerejodesimiwop.pdfIn PDF document text
    • http://www.ddd-iasi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16084d02960349---59826526247.pdfIn PDF document text
    • http://kazenergy.kz/wp-content/plugins/formcraft/file-upload/server/content/files/160bd3a3aea9aa---kivozusaxifiker.pdfIn PDF document text
    • https://mps-india.com/userfiles/files/42656274724.pdfIn PDF document text
    • http://terralis.eu/catalogue_dynamique/file/ninepudepumilezibez.pdfIn PDF document text
    • http://www.ncstarim.com.tr/wp-content/plugins/super-forms/uploads/php/files/r5a6ihoiqmi2apshj9fsehqb04/1259977709.pdfIn PDF document text
    • https://www.emma-solutions.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608ac45b3ee0b---nejivuneludiregitufedo.pdfIn PDF document text
    • https://sumangold.net.vn/wp-content/plugins/super-forms/uploads/php/files/17au3ggqq11u1mbt8m13h461j0/31257041830.pdfIn PDF document text
    • https://webgirls-studio.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608172a95e203---jemerutaxibo.pdfIn PDF document text
    • http://faxik.ru/ckfinder/userfiles/files/31219645527.pdfIn PDF document text
    • https://santehsevast.ru/userfiles/files/18564850720.pdfIn PDF document text
    • https://www.areatransfers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aa12a470933---1234789328.pdfIn PDF document text
    • http://osullivanspressurewashing.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b067f4bd8e6---25253376214.pdfIn PDF document text
    • http://xn--80aejmo0alc.xn--p1ai/ckfinder/userfiles/files/78926957806.pdfIn PDF document text
    • https://kachhiproperties.com/wp-content/plugins/super-forms/uploads/php/files/3np1i9o7jkc4c2g529ur0rorq4/lanimeturuxumuliwinuvubuj.pdfIn PDF document text
    • http://caphegiabao.com/upload/fck/file/58680360671.pdfIn PDF document text
    • http://scpt.it/userfiles/files/temufenijizodebodix.pdfIn PDF document text
    • https://laptoptranganh.com/data/dulieu/files/25639113658.pdfIn PDF document text
    • http://tcihk.com/userfiles/renemosugorinune.pdfIn PDF document text
    • http://rollfactorytogo.com/uploads/files/relofurunosigovitud.pdfIn PDF document text
    • https://aryaayur.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ce2a014449---10692830322.pdfIn PDF document text
    • http://ohana1bbq.com/uploads/files/melolunifozitutijo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=lions+club+international+logo+pdfPDF link annotation
    • http://crossfit28.com.s125853.gridserver.com/siteuploads/editorimg/file/3983816362.pdfIn PDF document text
    • 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_off0000d86d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD86D 10992 bytes
SHA-256: e539554ae8373a124440e2ddf34381ba9221c73b33922e02d146889afd4633ca
font_01_sfnt_off0000f1ac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1AC 19036 bytes
SHA-256: b81bbe4d4e42e8e4526ac41a4669243410c61c070a51940b18dda696af20d5ee
font_02_sfnt_off0001229b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1229B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1