Malicious PDF — malware analysis report

Static analysis result for SHA-256 0bc8d02138fdead1…

MALICIOUS

PDF

93.8 KB Created: 2021-09-02 01:51:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: c7502371a85a851a8bd475abe62e1655 SHA-1: 3b1201860f0862e8bd4e7eafec6a949bf174491d SHA-256: 0bc8d02138fdead192cb667c9f3714fc928ca41033980af7ca8284101cdabcb5
156 Risk Score

Malware Insights

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

The PDF file was flagged as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, directing users to multiple external URLs, many hosted on compromised WordPress sites or disposable domains. The presence of 'utm_term' parameters suggests a potential phishing or SEO-based lure to drive traffic to these sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9988

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://krisoc.ru/uplcv?utm_term=how+to+draw+a+hand+on+a+person PDF link annotation
    • https://asaptransfers.co.uk/wp-content/plugins/super-forms/uploads/php/files/aa3m0bg4vodh1hjvk810c48dn2/bubovosolujetiwupowuviwek.pdfIn PDF document text
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/f789jvjh40qcrm8pmitmbbp2f3/pasubowemikopexo.pdfIn PDF document text
    • http://cnex.cc/images/blog/file/mipopoxexubeg.pdfIn PDF document text
    • https://mcdpiti.com/userfiles/files/21445848322.pdfIn PDF document text
    • https://peiitw.com/Upload/ckeditor/files/takatanemibovilaruxejini.pdfIn PDF document text
    • https://chamsocmuihong.com/wp-content/plugins/super-forms/uploads/php/files/5ecevc2mmu365hhtvqhmtlkjc8/71061243928.pdfIn PDF document text
    • http://flywings.sk/UserFiles/file/mowoduxoxozilapefun.pdfIn PDF document text
    • https://machinex-machines.com/UserFiles/File/71190046670.pdfIn PDF document text
    • https://fjordancv.info/wp-content/plugins/super-forms/uploads/php/files/6ba123f64d9c65f1cb0a8a06c0c44696/63351769147.pdfIn PDF document text
    • http://www.sunarozlem.com.tr/wp-content/plugins/super-forms/uploads/php/files/qd32np4hegij7vh4u90mut8p01/99956793697.pdfIn PDF document text
    • http://drironcat.com/images/file/58474040865.pdfIn PDF document text
    • http://www.marcado.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160a16a4ea9add---31274024627.pdfIn PDF document text
    • http://rcp-ranstadt.us/files/59379144198.pdfIn PDF document text
    • https://asaptransfers.co.uk/wp-content/plugins/super-forms/uploads/php/files/9djh5b0o3iuuu3e7g0arhd6gi1/gozuzibolasodadutupivinuf.pdfIn PDF document text
    • https://robertmatzuzi-massagetherapist.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160bdd21c44234---nusutes.pdfIn PDF document text
    • http://sinocelltech.com/filespath/files/20210821003442.pdfIn PDF document text
    • https://psfund.org/public/uploads/files/cms_files/vovuze.pdfIn PDF document text
    • http://ks-puyuma.com/CKEdit/upload/files/40649029908.pdfIn PDF document text
    • https://ovth.ch/userfiles/files/45838505367.pdfIn PDF document text
    • http://www.fliesen-brill.de/wp-content/plugins/formcraft/file-upload/server/content/files/16123ca5115ed0---palatizetefedabumatu.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_off00010bec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10BEC 17792 bytes
SHA-256: 8fcfd4fccf7fc7f0dc5510ef36ff11077c98ee43b200ff7c9e9351e071f8075c
font_01_sfnt_off00013a41.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13A41 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00015258.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15258 10428 bytes
SHA-256: 4c4ce891dc9f1fd1e2500f42ec430accbf4bf969572df7bbb62504093ed5cd2e