Malicious PDF — malware analysis report

Static analysis result for SHA-256 772421a621f81e7e…

MALICIOUS

PDF

81.0 KB Created: 2021-07-07 01:36:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: d35deb272bf78ac693b496c30563c535 SHA-1: 1da3bd209510571f8938d932d6024d3a014e7804 SHA-256: 772421a621f81e7ef5a27af360cb5d0b1316c741d044aecf71c74ed65c812e07
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains a link farm pointing to numerous distinct hosts, many of which appear to be compromised WordPress sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. The presence of multiple PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics further supports this, suggesting the document's primary purpose is to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9950

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://www.mondzorgvesa-voorschoten.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16071c05513cf1---56511310800.pdf In PDF document text
    • http://www.tif.cn/wp-content/plugins/super-forms/uploads/php/files/tro89e2oivm57dneisjopp4lr1/bukiwuvuzuku.pdfIn PDF document text
    • https://connect.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/87102b31425489c25d3a7fcdf617e487/5061688916.pdfIn PDF document text
    • https://canionglobal.com/FCKeditor/file/80999701467.pdfIn PDF document text
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609851517b623---xuzukusefomeviv.pdfIn PDF document text
    • https://beaufortbond.com/wp-content/plugins/super-forms/uploads/php/files/b7fadcd205b39c1e13415aedeaa19903/mefezovekedeli.pdfIn PDF document text
    • https://sitebyside.ru/wp-content/plugins/super-forms/uploads/php/files/d14b3d0c25b187733cdc840d8d94e8aa/momilixapi.pdfIn PDF document text
    • http://jghsclass75.com/clients/f/f3/f322050927ea28328664fd088939ffaa/File/35379202953.pdfIn PDF document text
    • http://xenangheli.vn/public/files/xivifebog.pdfIn PDF document text
    • http://amdind.com/userfiles/file/67828631722.pdfIn PDF document text
    • http://614move.com/clients/4890/File/pujasajoranutirap.pdfIn PDF document text
    • http://www.vivelamusica.es/wp-content/plugins/formcraft/file-upload/server/content/files/16081b1fbc9c12---19496640118.pdfIn PDF document text
    • http://iviltra.lt/images/files/telenamoribusodajopolex.pdfIn PDF document text
    • https://auto-rujo.com/images-editor/file/nerolavubipevetesa.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160965f517d9b8---nipepatawawus.pdfIn PDF document text
    • https://sumangold.net.vn/wp-content/plugins/super-forms/uploads/php/files/jgtjchgq1lm0juc20kltfe6n6o/17350921891.pdfIn PDF document text
    • https://agsposure.org/wp-content/plugins/super-forms/uploads/php/files/51a460aa12b06bea35afd8e35fc6d1ab/veluduvokikasadodidorufal.pdfIn PDF document text
    • http://thecreditcrisis.net/clients/73966/File/78851818070.pdfIn PDF document text
    • https://vuaship.com/wp-content/plugins/super-forms/uploads/php/files/j65plbqke51c861thunql6epf4/zalemugupesezo.pdfIn PDF document text
    • http://thefutureofgolf.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160ad5c1343381---sivodade.pdfIn PDF document text
    • https://rhagro.com.mx/wp-content/plugins/super-forms/uploads/php/files/31ce4f9f8d2f5ff0411a6e9b9e0278ab/dunipulutobowopotuleg.pdfIn PDF document text
    • http://curry-box-deluxe.de/userfiles/file/tobinawo.pdfIn PDF document text
    • http://apexnepaltravel.com/userfiles/file/37176347452.pdfIn PDF document text
    • https://www.tessilgiada.it/wp-content/plugins/formcraft/file-upload/server/content/files/1609b38200eaad---6606510200.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=how+meaning+in+marathiPDF 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_off0000d3e4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD3E4 19232 bytes
SHA-256: caa8187a969154b6551aa8b1c804c0106d52e0a92ff85011789f6b44c900d7ae
font_01_sfnt_off00010611.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10611 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011e28.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E28 10420 bytes
SHA-256: d5ef5679ff61c049ce3d60ec77032c9f89084f659dd5dadfd6068a7801878287