Malicious PDF — malware analysis report

Static analysis result for SHA-256 8fc28fe1d5572e1e…

MALICIOUS

PDF

93.2 KB Created: 2021-06-13 05:46:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-24
MD5: 5b0a5032929ea2d564ce61c7a78ba216 SHA-1: cf97d620fb0659afcd7d416a96e0f9da34f9e848 SHA-256: 8fc28fe1d5572e1e0f1557ff68f7aaa04477e42551e38a5aa445ff660d1cd746
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://queure.ru/uplcv?utm_term=is+greaseproof+paper+the+same+as+freezer+paper PDF link annotation
    • http://securitydirect.it/wp-content/plugins/super-forms/uploads/php/files/2870f99bf40471f495013043776ecb79/51052824632.pdfIn PDF document text
    • http://barrarioservicos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a26cde59899---derulenudejikezeveb.pdfIn PDF document text
    • http://lbs.ac.at/wp-content/plugins/super-forms/uploads/php/files/os73ars73m6s40o7tslle96cn2/zosewut.pdfIn PDF document text
    • http://nguoigiupviec99.com/webroot/img/files/xerefebokig.pdfIn PDF document text
    • https://thejasmineway.net/wp-content/plugins/super-forms/uploads/php/files/hse3da41lbj3avbk9hove41tcs/wufiwuloxenu.pdfIn PDF document text
    • https://www.tangelo.no/wp-content/plugins/formcraft/file-upload/server/content/files/16071b80c8fcf4---98820936359.pdfIn PDF document text
    • https://gtsonline.nl/wp-content/plugins/super-forms/uploads/php/files/lfkc31ng510hjl83ut377vgs6r/nebuzanojeregutegel.pdfIn PDF document text
    • https://greyquotient.com/wp-content/plugins/super-forms/uploads/php/files/462b995c7633ba9a370784d6ac49dfa3/vanopajoximagugesimiraduf.pdfIn PDF document text
    • https://k9-warrior.com/wp-content/plugins/super-forms/uploads/php/files/36poceph5o0trvb9h96l31h8tu/96445592102.pdfIn PDF document text
    • http://learnazia.com/fck/imagesfile/58890765471.pdfIn PDF document text
    • http://humanitool.ru/userfiles/file/vorapezidumukaxeto.pdfIn PDF document text
    • https://bjjewels.net/nbloom/fckuploads/file/25522391248.pdfIn PDF document text
    • http://amtusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b8b6d0aa839---98936331488.pdfIn PDF document text
    • http://schouteninterieurwerk.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607622f830e69---81391594083.pdfIn PDF document text
    • https://stiff.pl/ckfinder/userfiles/files/wepawutuxu.pdfIn PDF document text
    • https://beautifullifeuk.com/wp-content/plugins/super-forms/uploads/php/files/4d34895c9d97c11bbc9209ec17086f3e/93612646972.pdfIn PDF document text
    • https://harpethvalleypto.org/wp-content/plugins/super-forms/uploads/php/files/fc76ba3f79451267c48c7380dc4305b8/nukanegozegomapobora.pdfIn PDF document text
    • http://www.emporiocaritaspisa.it/wordpress/wp-content/plugins/formcraft/file-upload/server/content/files/16092439651a62---gilizexuji.pdfIn PDF document text
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/160720a7b8a94f---66316559535.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00012363.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12363 4904 bytes
SHA-256: 7a89cadf094bc2facc834eda09b569287e4e3f428c0e7f844c0a318ac7706b31
font_01_sfnt_off00013414.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13414 11108 bytes
SHA-256: 904fa81db10ee54c54f7b296b3b4a1712221c05c7b623d5c060ae464534b8131
font_02_sfnt_off00015980.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15980 4324 bytes
SHA-256: cd94ef65598b1866d0653cdd88243d989fd81359c0e770c2d3a4858f1c2f6d34