Malicious PDF — malware analysis report

Static analysis result for SHA-256 c4701a016c1e8197…

MALICIOUS

PDF

70.8 KB Created: 2021-09-19 09:35:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 1bc0c9d3644e25a9c5414738bea193b0 SHA-1: 9a12484cb95fc8dbcb6d13e7cb11d7c4b7bec3bd SHA-256: c4701a016c1e81972a7310230093a3014b7f7c891244223fe0df8fecd40e2506
156 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate the presence of a link farm pointing to various websites, including those hosted on compromised CMS platforms, suggesting an attempt to direct users to malicious content or downloads. The presence of multiple PDF_URI and PDF_SEO_DISPOSABLE_LINK_FARM heuristics further supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://dyaa.club/uploads/file/nuselifalafanum.pdf In PDF document text
    • http://scuolascifondocortinadolomiti.it/userfiles/files/59760976408.pdfIn PDF document text
    • https://thuaphatlaihoanghuy.com/uploads/files/doviposobiba.pdfIn PDF document text
    • https://www.spoton.pet/wp-content/plugins/super-forms/uploads/php/files/obstsqj4qlb4bvo6iq2jv86ucl/lometitegosezotapirez.pdfIn PDF document text
    • http://urdu-hadith.com/survey/userfiles/files/pulawabipuw.pdfIn PDF document text
    • https://cvenhancer.com/wp-content/plugins/super-forms/uploads/php/files/71c26f263b167b724480e8b2d1ac6bc9/91390940123.pdfIn PDF document text
    • http://katyababash.com/images/uploads/file/43014084270.pdfIn PDF document text
    • https://rajakeempat.com/contents/files/rowiluwugizuxemikosenomub.pdfIn PDF document text
    • http://riverside-plaza.com/upload/userfile/files/41260438094.pdfIn PDF document text
    • http://cu-mbc.com/ckfinder/userfiles/files/48419747067.pdfIn PDF document text
    • http://flagrant-desir.com/userfiles/file/75581174181.pdfIn PDF document text
    • http://stilna-ya.com/_userfiles/file/bopoze.pdfIn PDF document text
    • http://gdlejia.com/uploadfile/files/20210905_014423.pdfIn PDF document text
    • http://netdepphunu.vn/images/userfiles/file/kimovu.pdfIn PDF document text
    • https://thefencedocumentary.com/adminfiles/file/bewowixi.pdfIn PDF document text
    • http://rescue119.org/userfiles/file/8136862651.pdfIn PDF document text
    • https://sweetestspaparty.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f7e398f239---pexodazafasosivarobezezib.pdfIn PDF document text
    • http://nova-auto.com/upload/879991647.pdfIn PDF document text
    • http://avvolodin.ru/upload/file/47781022113.pdfIn PDF document text
    • http://sibinetweek.ru/userfiles/file/13779048094.pdfIn PDF document text
    • https://equimat-cheval.fr/file/21695963446.pdfIn PDF document text
    • https://iwistw.com/upload/files/wokajamerotomifadowodev.pdfIn PDF document text
    • http://occahomesearch.com/userfiles/files/70199430059.pdfIn PDF document text
    • http://www.eurosecurimed.com/ckfinder/userfiles/files/30777776911.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=dead+trigger+2+free+downloadPDF 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_off0000b722.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB722 10568 bytes
SHA-256: 347e10d260987d289faa80c5a674c60be4f67e85a3cd3da193a67fc70c3fbc94
font_01_sfnt_off0000cf3b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF3B 15244 bytes
SHA-256: 302d2c472756c544187e4e0c7ca0bca699c9897b37ac1e9b2772493b9344f17b
font_02_sfnt_off0000f5dc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5DC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1