Malicious PDF — malware analysis report

Static analysis result for SHA-256 f944350e3e1d83dc…

MALICIOUS

PDF

71.6 KB Created: 2021-09-28 07:35:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: f4b48c597268ba1bea99c382196d3ecc SHA-1: 5dd0e26bf780fb97df4a4e0d84f0e57172cc9022 SHA-256: f944350e3e1d83dc779d62c66878f853db3d16fef2b0e5bbc114c19bdf9c4e66
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains multiple links to external websites, many of which are hosted on compromised WordPress sites or disposable domains, suggesting a link farm for phishing or malware distribution. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or trojan delivery. Although no scripts were explicitly extracted, the PDF structure and embedded URLs point towards a malicious lure designed to redirect users to harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9909

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://coretry.ru/uplcv?utm_term=pokemon+heartgold+game+download PDF link annotation
    • http://www.sbawerribee.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/161503d4c8fc49---80320305069.pdfIn PDF document text
    • http://rockhousemethod.com/ckfinder/userfiles/files/61605606315.pdfIn PDF document text
    • https://jobtiara.com/files/files/17866710576.pdfIn PDF document text
    • http://www.cenlafilm.com/siteuploads/editorimg/file/43217168389.pdfIn PDF document text
    • https://gruntbudowa.pl/files/file/vejujon.pdfIn PDF document text
    • http://toflight.mobi/attachment/ckeditor/files/48824148958d66aa76cfd133900afa0b.pdfIn PDF document text
    • https://charming-dc.com/uploads/files/202109210551577073.pdfIn PDF document text
    • http://tatishev.ru/admin/ckfinder/userfiles/files/97908202340.pdfIn PDF document text
    • https://cungcapthitdetuoi.com/app/webroot/files/images/pages/files/87810169602.pdfIn PDF document text
    • http://www.sport-konyv.hu/userfiles/file/16826225859.pdfIn PDF document text
    • http://huucodatlanh.com/userfiles/file/51659586079.pdfIn PDF document text
    • https://camile.vn/wp-content/plugins/super-forms/uploads/php/files/hpjtm0mla0d4jgvnuk3qru8jl1/59150575943.pdfIn PDF document text
    • http://alexdisinfestazioni.com/userfiles/files/zokogidaburonepipepu.pdfIn PDF document text
    • http://duszek-lasu.pl/userfiles/file/kupazigamakulu.pdfIn PDF document text
    • http://przedszkolenisko.pl/userfiles/file/murovujunobevemaditigin.pdfIn PDF document text
    • http://baggiez.net/userfiles/file/mipaxeduguwijomaj.pdfIn PDF document text
    • http://www.romanschatztruhe.de/img/files/97224878033.pdfIn PDF document text
    • http://www.solarwindependence.com/ckfinder/userfiles/files/pijozevezudomubomu.pdfIn PDF document text
    • http://silverk.ru/img/lib/file/94049700552.pdfIn PDF document text
    • http://www.oknookna.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1614f62439fd33---getelosuraku.pdfIn PDF document text
    • https://www.grandiosa.is/wp-content/plugins/super-forms/uploads/php/files/4buq0im10ifq0q5jn433bdb2m3/simagimilatifi.pdfIn PDF document text
    • http://curry-box-deluxe.de/userfiles/file/tinuw.pdfIn PDF document text
    • http://subventionsbetrug.de/wp-content/plugins/super-forms/uploads/php/files/8dqnqvlqeh42k8bqe09qkt5qbc/9695777912.pdfIn PDF document text
    • https://thewentworthco.com/wp-content/plugins/super-forms/uploads/php/files/ghtoj9u5s5npn4dclta3mgrkqc/87890640611.pdfIn PDF document text
    • https://marksiegeldds.com/wp-content/plugins/super-forms/uploads/php/files/d9a5e285f7f1c697c3dbbc900c952026/40563841898.pdfIn PDF document text
    • http://vdgairconditioning.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613fd7d45ccac---zusere.pdfIn PDF document text
    • http://apex-architect.ru/images/file/fewadobogekedafatiburu.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_off0000b6ed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB6ED 16200 bytes
SHA-256: 3dd707ed7569624e3b4d2671253614f3fa5b3da2148343c795b0e703dac06afa
font_01_sfnt_off0000e003.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE003 10616 bytes
SHA-256: 4d8415e4e2cfd7ca83bfe6ed1c050d3df076ea3451349a43da152c0546d2f0fb
font_02_sfnt_off0000f7f4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7F4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1