Malicious PDF — malware analysis report

Static analysis result for SHA-256 a6f4a78e73431068…

MALICIOUS

PDF

81.4 KB Created: 2021-09-21 13:18:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: b3be65ddf17b8768e57518487c4dbc0f SHA-1: e0653e37bd355f9c810b9dba76305f586fc50354 SHA-256: a6f4a78e73431068d147e34eeffec14e7d766fb938e2eb217f2ff024369fe41b
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites acting as link farms. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware distribution. The presence of 'utm_term' parameters in some URLs suggests a campaign-like structure aimed at tracking user engagement.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://allytemp.ru/uplcv?utm_term=lector+pdf+para+android PDF link annotation
    • https://trucraftsmanship.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614936fb6f661---13686483250.pdfIn PDF document text
    • https://www.suep.gr/ckfinder/userfiles/files/rutuboredobizazanuvasalu.pdfIn PDF document text
    • http://jockmurray.com/wp-content/plugins/formcraft/file-upload/server/content/files/161484aa320a8e---muwenezozukoxajel.pdfIn PDF document text
    • http://studiopiergentili.it/userfiles/files/wuxagu.pdfIn PDF document text
    • http://paraleumarian.ro/app/webroot/files/userfiles/files/lapodozefu.pdfIn PDF document text
    • http://didopack.com/files/83416819921.pdfIn PDF document text
    • http://www.saveurspoitoucharentes.com/admin/ckfinder/userfiles/files/94581391906.pdfIn PDF document text
    • http://patrick-vallot.com/upload/files/45423216840.pdfIn PDF document text
    • https://harrisitalia.it/uploads/file/59557840601.pdfIn PDF document text
    • https://agronlogistics.com/userfiles/files/sivosanojifevimukife.pdfIn PDF document text
    • http://whuntex.ru/userfiles/file/biduxi.pdfIn PDF document text
    • http://mega.kz/media/upload/files/tijuvoda.pdfIn PDF document text
    • http://back2wood.de/userfiles/file/kogilovujafeniw.pdfIn PDF document text
    • http://szyqjsj.com/UploadFile/file/20210917012508214.pdfIn PDF document text
    • https://darshanam.com/ckfinder/userfiles/files/23009700457.pdfIn PDF document text
    • http://carlaschroyen.com/content_docs/nenemagudusawesu.pdfIn PDF document text
    • http://rdasesores.gestconcursal.com/editor/ckfinder/userfiles/files/88792427165.pdfIn PDF document text
    • http://kccmaul.com/files/files/41409993695.pdfIn PDF document text
    • https://cncunse.com/d/files/51089260573.pdfIn PDF document text
    • http://allgeology.ru/ckfinder/userfiles/files/vubel.pdfIn PDF document text
    • https://togeltop.com/contents/files/84763597675.pdfIn PDF document text
    • https://optimuselearningschool.com/learning/site/images/uploadfiles/27568182137.pdfIn PDF document text
    • http://www.next-conseil.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1613319e60224f---nikagofaribovofuxeneguxol.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_off0000d971.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD971 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f183.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF183 18028 bytes
SHA-256: 0752e3e61f9e5fdd31fcab1dc53f7abd7a63c3091bfa30f73a452a333c54df7d
font_02_sfnt_off00012041.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12041 10356 bytes
SHA-256: 8a884ac9bf2337b4e53f4988eae340b17564c14f3932a3babf5b6c8ac78b431f