Malicious PDF — malware analysis report

Static analysis result for SHA-256 a576edcf3ee10212…

MALICIOUS

PDF

106.3 KB Created: 2021-09-07 14:46:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 0003e2b9b5c1cf45b303f7fe983448e3 SHA-1: 60809879af90adfbadcd2caa9d9682f14eb2105f SHA-256: a576edcf3ee10212f29703ffc9289edbb3ed23d0a443a0c6a52a43983c18f09f
156 Risk Score

Malware Insights

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

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with many embedded URLs pointing to compromised WordPress sites and disposable hosting. The document body is heavily obfuscated, preventing analysis of its specific content, but the overall structure suggests a lure to trick users into visiting external 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://sumangold.net.vn/wp-content/plugins/super-forms/uploads/php/files/l71qas6p5nc7m0s2r68kqighom/repoluroz.pdf In PDF document text
    • http://nitexprofi.cz/userfiles/file/48549956918.pdfIn PDF document text
    • http://jinruily.com/UploadFile/file/20210801234228996.pdfIn PDF document text
    • https://suemsas.com/wp-content/plugins/super-forms/uploads/php/files/seuloh2qau5hiv602306im82b7/22124449047.pdfIn PDF document text
    • http://www.qookspot.kitchen/wp-content/plugins/formcraft/file-upload/server/content/files/1609c87009180e---10828736217.pdfIn PDF document text
    • http://dealershop.es/camarasegovia/userfiles/file/57022859194.pdfIn PDF document text
    • http://jaatkinson.com/userimages/69748547472.pdfIn PDF document text
    • https://remoteyourstaff.com/calisma2/files/uploads/46510345917.pdfIn PDF document text
    • https://fsbulletsandbrass.com/userfiles/files/39835324861.pdfIn PDF document text
    • https://lokmangal.co.in/wp-content/plugins/super-forms/uploads/php/files/56a1da335062ebb12f6d3d5270911df9/nalalad.pdfIn PDF document text
    • http://tunglamgarden.com/images/fck/file/70043227635.pdfIn PDF document text
    • https://heatingboiler.ca/fck_upload/file/793543296.pdfIn PDF document text
    • https://songod.vn/uploads/image/files/10017357598.pdfIn PDF document text
    • http://wingprocess.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/medufepakiwulosutakixol.pdfIn PDF document text
    • https://icbacademy.com/upload/files/20451235863.pdfIn PDF document text
    • https://www.movingwithmagna.com/wp-content/plugins/super-forms/uploads/php/files/d3c1fc987d1ba8c977c13a3d688b24c0/bunokog.pdfIn PDF document text
    • http://cartopack.com/Images/file/vojozurufadux.pdfIn PDF document text
    • http://brainbond.ro/userfiles/file/90103916944.pdfIn PDF document text
    • https://www.toptalentusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608cb7daaf026---32543417418.pdfIn PDF document text
    • http://www.tif.cn/wp-content/plugins/super-forms/uploads/php/files/jpndvqauops99e4pc9cvd9mog2/damoge.pdfIn PDF document text
    • https://x-software.cz/data/file/demife.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=searching+for+alaska+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_off000137de.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x137DE 10968 bytes
SHA-256: 3fb5c200ca70525fdc849b81a34967cfe32f2a0bc98376f93f3e8b6cf30ac640
font_01_sfnt_off00015100.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15100 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00016912.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16912 19416 bytes
SHA-256: 9016082eb0d447424d434a6c937328086361c24fd1ce46ebde495e88064d70ae