Malicious PDF — malware analysis report

Static analysis result for SHA-256 413d1a4312d98cee…

MALICIOUS

PDF

79.5 KB Created: 2021-07-08 07:55:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: 1bd8510fc5cedaa0f8acd2cb9ead7bfa SHA-1: ef5a6ef6a230d994ba85c95bf988fe2dcf616435 SHA-256: 413d1a4312d98cee731445bbdbac93383ed70acb1cd2a02a40b2736ac504e54c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm with numerous URLs pointing to external resources, many hosted on compromised or disposable domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. While no scripts were explicitly extracted, the PDF structure and embedded URIs suggest it's designed to lure users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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 https://alenakovalchuk.ru/wp-content/plugins/super-forms/uploads/php/files/fc3d54feb63b2f0896134e0e9efbd42b/mexodi.pdf In PDF document text
    • https://christianboudreau.com/wp-content/plugins/formcraft/file-upload/server/content/files/160947d4b88b96---46883757063.pdfIn PDF document text
    • https://szaniterplaza.hu/ckfinder/userfiles/files/likilidufowulewawetawa.pdfIn PDF document text
    • http://www.studiolegalefusimorelli.com/wp-content/plugins/formcraft/file-upload/server/content/files/160751f85dd23a---pobedomiwepagigafivin.pdfIn PDF document text
    • https://astoriareiki.com/wp-content/plugins/super-forms/uploads/php/files/eb2813af6f6d29e9b5a2214bb72385e8/xurodovalulufadesu.pdfIn PDF document text
    • http://allasclub.com/campannas/file/domeji.pdfIn PDF document text
    • http://sieckultury.pl/wp-content/plugins/super-forms/uploads/php/files/535533331e980d3b9ab0277a9e5af8f9/xugaxusixabi.pdfIn PDF document text
    • https://www.kiteschule-eckernfoerde.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609a48a99f113---26979741549.pdfIn PDF document text
    • http://naucseto.cz/storage/41390911566.pdfIn PDF document text
    • https://mamproducciones.es/wp-content/plugins/formcraft/file-upload/server/content/files/160abaa50d5ea8---86227146002.pdfIn PDF document text
    • https://sofanet.ro/ckfinder/userfiles/files/puful.pdfIn PDF document text
    • http://www.phonefixcomo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160908ec52dfd3---sinalo.pdfIn PDF document text
    • http://studiorumeo.it/userfiles/files/60359639091.pdfIn PDF document text
    • http://cityclick.it/userfiles/files/fakeravudawobinuv.pdfIn PDF document text
    • https://bf-pomosch.ru/wp-content/plugins/super-forms/uploads/php/files/o87qf538fvjb2opm52njp2c4a0/kotokef.pdfIn PDF document text
    • https://www.sabiamente.es/wp-content/plugins/formcraft/file-upload/server/content/files/1606d4561b9ca4---55990206110.pdfIn PDF document text
    • http://kirilmazbardak.com/userfiles/file/38189612553.pdfIn PDF document text
    • https://lisacutler.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608a3dedc3b6a---xiresaxuwowujivuxuxa.pdfIn PDF document text
    • https://cutletsmeat.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608c1edd5ee72---rijibelilavoga.pdfIn PDF document text
    • http://clinicacomciencia.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607783ebaedac---nilenaponavew.pdfIn PDF document text
    • http://www.kinoimaging.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160a5a3deeb478---68767576804.pdfIn PDF document text
    • https://amalighting.com/wp-content/plugins/super-forms/uploads/php/files/dde0ac7b781b6b5d867a1a83f8300f88/1538902085.pdfIn PDF document text
    • http://wakingbeauty.com/wp-content/plugins/formcraft/file-upload/server/content/files/160962eab1ba1b---98246189114.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=computer+parts+and+their+functions+pdfPDF 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_off0000d5cf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD5CF 16120 bytes
SHA-256: 95b73d9a2e1d2c66687d5ab7c3dc774d7a88b2bed8561c9b445957ebb2b2d439
font_01_sfnt_off0000ff61.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF61 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011778.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11778 10972 bytes
SHA-256: 9e6c2fc225efc04268ff86d3527d5705dcecebb7641c1d11968ca7c25bc7bacf