Malicious PDF — malware analysis report

Static analysis result for SHA-256 4247ace4b51a0b2a…

MALICIOUS

PDF

75.0 KB Created: 2021-09-07 23:31:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: a4e1e7dffdab7fabe6c77748a83e9dab SHA-1: 515d6d70a7c9c214989ea5b2e737b24b9fe4e38d SHA-256: 4247ace4b51a0b2a24a46310b12a2d550ffca025f7fe91c079c6ab7630567caa
156 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs, many of which point to compromised WordPress upload directories and disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. The document body is unreadable, but the heuristic firings suggest a link farm designed to lure users to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9971

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://graphicon.hu/wp-content/plugins/formcraft/file-upload/server/content/files/16077eb82415c9---44450458324.pdf In PDF document text
    • http://111-orte.de/testarea/cwsCMSlight/media/files/16176505889.pdfIn PDF document text
    • https://leuphuotcamap.com/uploads/image/files/rezofimipowexexo.pdfIn PDF document text
    • http://patrickstaxi.fr/userfiles/file/jidunozomitazunizulave.pdfIn PDF document text
    • https://christembassyromford.org/wp-content/plugins/super-forms/uploads/php/files/0dc532d9cc4ff08095f842cd62ef0b8c/wipari.pdfIn PDF document text
    • https://farmstead.tw/farmstead/upload/files/femadawodixezomad.pdfIn PDF document text
    • http://www.dreamstoreonline.es/ckfinder/userfiles/files/nijofivizeriwarenem.pdfIn PDF document text
    • http://aven.su/userfiles/file/50987719211.pdfIn PDF document text
    • https://ego-sofa.tw/uploads/files/202109011329494184.pdfIn PDF document text
    • https://mtydizayn.com/userfiles/file/dowalupadovopubovoninaro.pdfIn PDF document text
    • http://rexant.by/upload/editor/files/18255763408.pdfIn PDF document text
    • http://discarga.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aa3cbfc57df---8339941547.pdfIn PDF document text
    • http://www.laterveer-biesenbeek.nl/ckfinder/userfiles/files/legopetonanon.pdfIn PDF document text
    • http://glamour-nsk.ru/ckfinder/userfiles/files/zaxusojojikukumupiwul.pdfIn PDF document text
    • http://www.tsssport.com/wp-content/plugins/formcraft/file-upload/server/content/files/16091146a4d47a---wawutomipawexomet.pdfIn PDF document text
    • https://ferest.ro/imagini_ws/tizabapipejaxis.pdfIn PDF document text
    • https://groupunsur4.com/contents//files/7175569110.pdfIn PDF document text
    • http://intertexmedical.com/userfiles/files/saboxukiwe.pdfIn PDF document text
    • http://limpiasol.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a2b3d48dcec---70564865998.pdfIn PDF document text
    • http://objetivovender.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c51dfbb95fd---fitovojuzasakumugerotuda.pdfIn PDF document text
    • http://sanmarinreunion.com/clients/c/c0/c0747301521b2fcd71a0106c9132c7e7/File/genunutege.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=ibadat+harian+katolik+pdfPDF 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_off0000c352.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC352 16984 bytes
SHA-256: 0ebf1d93ac7725d9d2f3340111817df6d30ba2cf92435fdcad075ce06e91adb6
font_01_sfnt_off0000ef59.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF59 10480 bytes
SHA-256: 35c1d0416263eccb1551833b7d3d2bff7322e59e921971d86b7bd2d1d9f01d08
font_02_sfnt_off000106c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106C6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1