Malicious PDF — malware analysis report

Static analysis result for SHA-256 76070d4b53a17113…

MALICIOUS

PDF

68.4 KB Created: 2021-09-28 09:35:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: d8b266fe6dcb6cf069b42554f5d91581 SHA-1: f7badd2f61bd08139d6333b84d0ef13371b96d07 SHA-256: 76070d4b53a17113759825e6b54cba54109d2f8176f43e3163159a74c277ee56
156 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to compromised CMS uploads or disposable hosting, suggesting a link farm designed to redirect users to malicious sites. The document body is heavily obfuscated and unreadable, but the presence of external URI heuristics and link farm indicators strongly suggests a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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://ketchas.ru/uplcv?utm_term=bluelight+filter+ios PDF link annotation
    • http://canshu.dlzj.net/upload/files/20210917081541261932.pdfIn PDF document text
    • https://www.focus.mu/wp-content/plugins/super-forms/uploads/php/files/dc9279bfabb3035a65cf7d639e8ef1f3/34221031283.pdfIn PDF document text
    • https://pcparts.fr/ckfinder/userfiles/files/noraribojoganigawudigorad.pdfIn PDF document text
    • http://urdu-hadith.com/survey/userfiles/files/jilokozorovamido.pdfIn PDF document text
    • http://rotarytattoomachine.co/project-new/christianbook/upload_images/file/novox.pdfIn PDF document text
    • https://edouardweil.com/userfiles/file/naderebifisopodu.pdfIn PDF document text
    • https://malimbe.africa/wp-content/plugins/super-forms/uploads/php/files/afeae69b93dcebc73de3e9933377b615/41477405817.pdfIn PDF document text
    • http://getvisa.ru/images/File/bovufazoleg.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16147bbb66706d---50593402873.pdfIn PDF document text
    • https://jsptti.com/ckeditor/ckfinder/userfiles/files/zulugaxin.pdfIn PDF document text
    • https://hantverksakuten.se/ckfinder/userfiles/files/33128684793.pdfIn PDF document text
    • http://phongkhamthienhoa.vn/images/files/liwibilugasoze.pdfIn PDF document text
    • http://bachova-terapia.sk/images/file/76431750021.pdfIn PDF document text
    • http://europeanprofservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/161529e703be29---wapiralakiporanekakawome.pdfIn PDF document text
    • https://mkycc4.com/kycc4.com/userfiles/files/49828125031.pdfIn PDF document text
    • http://www.og2c.com/images/file/89139621173.pdfIn PDF document text
    • https://www.golddustdental.com/wp-content/plugins/formcraft/file-upload/server/content/files/16145e5e099ade---piwemenuwuvupeji.pdfIn PDF document text
    • http://tythb.cn/uploadfile/files/metegivuberalepewim.pdfIn PDF document text
    • https://thietbigas.net/media/files/15847636555.pdfIn PDF document text
    • https://technok.cz/wp-content/plugins/super-forms/uploads/php/files/d94d5b6ed2b6a88c7f1bc232e69f07d1/vepekojozonixoseva.pdfIn PDF document text
    • https://agmatbaa.com/upload/files/felukax.pdfIn PDF document text
    • http://luckysim.com/userfiles/file/98752297854.pdfIn PDF document text
    • https://i-intelli.com/ckfinder/userfiles/files/21381982731.pdfIn PDF document text
    • http://zhouzhuank.com/v15/Upload/file/202194235239955.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_off0000b00b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB00B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c81d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC81D 14640 bytes
SHA-256: 3660c4f33440e0316b8806845c58033438a0f3c6c4fdf768ba0fe2d961fe9ab5
font_02_sfnt_off0000ed06.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED06 10380 bytes
SHA-256: 1ffa7540533d5fe0700bdd8ada924af56ae0ccb22a275190464db01ceadffa13