Malicious PDF — malware analysis report

Static analysis result for SHA-256 d31c6841a8b597a1…

MALICIOUS

PDF

84.8 KB Created: 2021-06-26 15:20:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: cb82a4e1597a8c2c7d970f11c5b5ba8c SHA-1: 047d11deefa70c11826eb69e7d0a501827d4229c SHA-256: d31c6841a8b597a1fc468c544ca49c1216a2769a6eee39e1cb50dd4378ad68f8
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as a phishing trojan. It contains numerous external links, many pointing to compromised CMS upload storage or disposable hosting, suggesting a link farm or redirection mechanism. The presence of embedded URLs and the overall structure indicate an attempt to direct users to malicious external sites, likely for phishing or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://nomylo.ru/uplcv?utm_term=night+fishing+for+trout PDF link annotation
    • http://seoulmenu.com/uploads/files/3453068040.pdfIn PDF document text
    • https://vaytieudungtragop.com.vn/wp-content/plugins/super-forms/uploads/php/files/acr19a7fdmnc0e814cl3k6cnji/javuzaju.pdfIn PDF document text
    • https://spazmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607965160989d---difaxo.pdfIn PDF document text
    • http://escqatar.com/uploads/userfiles/file/file/60015491906.pdfIn PDF document text
    • https://sambelteri.com/contents//files/18950817435.pdfIn PDF document text
    • https://www.marbelitesa.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1607cb7c9d6374---fisafoji.pdfIn PDF document text
    • http://hi-reid-solutions.com/wp-content/plugins/super-forms/uploads/php/files/474f484af835236f23cd3c2dcf6497ca/33072949879.pdfIn PDF document text
    • https://homini.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1607fa985078c2---senojovatitalawu.pdfIn PDF document text
    • https://miamiuniquelimo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16099d15a8e48f---83128618818.pdfIn PDF document text
    • https://simondaulte.com/ckfinder/userfiles/files/86385150625.pdfIn PDF document text
    • https://vrindaindia.com/php/joseph/uploads/file/45865469758.pdfIn PDF document text
    • http://hattrick-sports.com/wp-content/plugins/formcraft/file-upload/server/content/files/160789d2b260b5---xuxizigafinekafufodamerok.pdfIn PDF document text
    • https://www.asahinafunnels.com/wp-content/plugins/super-forms/uploads/php/files/fj0ovjh3t3ua7cs8ovtsjuuegp/juposajalofoj.pdfIn PDF document text
    • https://www.hagensmarketing.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086a108704a6---gisaniruxebuziwepezowok.pdfIn PDF document text
    • http://thuocnam.xyz/images/files/99208589956.pdfIn PDF document text
    • https://nationalcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a77a4edeb45---80460689844.pdfIn PDF document text
    • http://tgtech-auto.com/userfiles/file/98457902629.pdfIn PDF document text
    • http://bjhtdszdh.com/v15/Upload/file/202152562147682.pdfIn PDF document text
    • http://beijinghuojia.cn/userfiles/file/46970342876.pdfIn PDF document text
    • https://binhruamuinanobac.com/wp-content/plugins/super-forms/uploads/php/files/at6voncdbmnfcv781ku2quhb21/36120844902.pdfIn PDF document text
    • https://wilsonbarrera.com/inicio/wp-content/plugins/formcraft/file-upload/server/content/files/160b75db4d538c---xegibosavilefadu.pdfIn PDF document text
    • http://passaicvalleyclassof1957.com/clients/44362/File/55352031383.pdfIn PDF document text
    • https://limpjet.com.br/wp-content/plugins/super-forms/uploads/php/files/0ce842f6e6c93cfa3635bcb4f3fa5447/2711256568.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_off0000eab1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEAB1 16580 bytes
SHA-256: a4272f70f8185124054d3837005b423c891c66d4a3547aba64c46d3e244046ff
font_01_sfnt_off0001159d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1159D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012db4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12DB4 10228 bytes
SHA-256: 400dba7b49d95420199293f09caf19e8b6b94aa7ac230c209f18c1fcf8f0438b