Malicious PDF — malware analysis report

Static analysis result for SHA-256 f13925db41c6ded9…

MALICIOUS

PDF

79.4 KB Created: 2021-09-05 05:07:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 272b09e1a7d1ad17eac2755a5e436efb SHA-1: 50fcf9e881c6f631e3664914e4c46fdf2076eb4a SHA-256: f13925db41c6ded9815aaa57804f0e0d4907c2f5af3ebebee0f6d7b867821c6d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of links, many of which point to compromised CMS upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent. The primary function appears to be acting as a link farm to distribute traffic to potentially malicious sites, leveraging compromised infrastructure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://mpressivelabels.com.au/application/third_party/ckfinder/userfiles/files/41903122687.pdf In PDF document text
    • https://mosoptagro.ru/wp-content/plugins/super-forms/uploads/php/files/590bd57058d221538d87b6fa6ecf84c8/85842446847.pdfIn PDF document text
    • https://avenirpourtous.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160b06dc789e7c---sotaritofo.pdfIn PDF document text
    • http://allmedicus.com/userfiles/file/vajegakaludepedemexalam.pdfIn PDF document text
    • http://tiramisu-o.com/yamituki-n/uploads/files/58356486035.pdfIn PDF document text
    • http://consulcongress.it/uploads/assets/file/mubek.pdfIn PDF document text
    • https://hanahana.vn/media/ftp/file/rosenewejidedik.pdfIn PDF document text
    • http://franceplus.fr/userfiles/file/lasuvogufusexiberemaben.pdfIn PDF document text
    • https://accesoriosalmayor.com/images/userfiles/file/44541463043.pdfIn PDF document text
    • https://amezdigital.com/wp-content/plugins/super-forms/uploads/php/files/fe95e9f5588186f772e8dc404cca47c6/witiwarezosaj.pdfIn PDF document text
    • http://hanhthien.net/uploads/file/piponatex.pdfIn PDF document text
    • https://acornschoolcharleston.org/wp-content/plugins/super-forms/uploads/php/files/2a4ed4a11315466e0dc6849ec46f7d08/42381390006.pdfIn PDF document text
    • http://vitajeans.com/ckfinder/userfiles/files/97445530905.pdfIn PDF document text
    • https://istanbularicilikfestivali.com/upload/ckfinder/files/xenarazir.pdfIn PDF document text
    • http://hasyo.net/files/file/77053246977.pdfIn PDF document text
    • http://christopherspubandgrille.com/userfiles/files/12156034111.pdfIn PDF document text
    • http://banglatalkies.com/dynamic-images/cms/file/lezurifodibiju.pdfIn PDF document text
    • http://aep-tc.com/cache/fck_files/file/45405175636.pdfIn PDF document text
    • http://gnatowski.pl/attachments/file/sozegofizosesibonegakiw.pdfIn PDF document text
    • https://laptopserwis.com/app/webroot/media/files/nupaduredisijilonol.pdfIn PDF document text
    • http://allegroescrow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cb7d927bc1---kijimezoj.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=construction+equipment+magazine+pdfPDF link annotation
    • https://mediaget.com/userfiles/files/70965328353.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_off0000d0a2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD0A2 11256 bytes
SHA-256: 53f92fc7bd4ea319829f72988e409791c8b8dff127661e36115993fb2d5a0118
font_01_sfnt_off0000ea9a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA9A 17708 bytes
SHA-256: a2a55c31e225a5f0da6e4074045adaab6a07a7070e4a7a13b53c0dfb298d293b
font_02_sfnt_off000117d4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x117D4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1