Malicious PDF — malware analysis report

Static analysis result for SHA-256 b559a800970de9dd…

MALICIOUS

PDF

81.8 KB Created: 2021-09-02 22:30:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 95a63426d2f31025c8a866b44df08a3d SHA-1: 5cf9548db35994f33e8d6d04dcfe832d6b16f33e SHA-256: b559a800970de9ddbfedbb46a9f17623adb06615b7ce85f2b5b8ed441c224b4e
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 various websites, including those hosted on compromised CMS platforms. The document body is heavily obfuscated, preventing a clear understanding of its specific lure, but the overall structure and detection results strongly suggest a malicious intent to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 http://fullcolorspandoeken.nl/userfiles/file/35172277503.pdf In PDF document text
    • http://bestapp4u.com/admin/uploadedfiles/file/vasitinemopibagulumesonon.pdfIn PDF document text
    • https://www.frontierexim.com/wp-content/plugins/super-forms/uploads/php/files/s3tr60dfg6suhosmgor3neb2ss/53744599771.pdfIn PDF document text
    • http://xn--aknmedcal-wpbe.com/uploads/file/34108229373.pdfIn PDF document text
    • https://lolakarimova.uz/ckfinder/userfiles/files/42907377089.pdfIn PDF document text
    • https://www.sistemkabin.com/ckfinder/userfiles/files/50686415242.pdfIn PDF document text
    • https://sanidom.pl/img/file/wowapiruwanilepenazij.pdfIn PDF document text
    • http://bagpack.com.np/wp-content/plugins/formcraft/file-upload/server/content/files/1607a1af94b690---nubuze.pdfIn PDF document text
    • https://bonacorsi.it/file/67260867352.pdfIn PDF document text
    • http://hattrick-sports.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609da7252fab4---nuxakemodi.pdfIn PDF document text
    • http://mamtaniketan.com/userfiles/file/garigezopufedojugunuxex.pdfIn PDF document text
    • https://kcss.hu/korosi/userfiles/file/waligozawajikunanufurebof.pdfIn PDF document text
    • http://toanlinh.vn/upload/files/fefubukazekadam.pdfIn PDF document text
    • http://savitapiti.org/ckfinder/userfiles/files/wijopetitebozaperujukepel.pdfIn PDF document text
    • https://cairparavel.ro/app/webroot/files/userfiles/files/8683389943.pdfIn PDF document text
    • https://www.jscorporation.co.in/wp-content/plugins/formcraft/file-upload/server/content/files/160841134ea720---kaban.pdfIn PDF document text
    • http://hillcountryawningsandsunscreens.com/wp-content/plugins/formcraft/file-upload/server/content/files/160782a5422159---32111759613.pdfIn PDF document text
    • http://alternatifmedikal.com/img/userfiles/files/niferumixobuvoxepabug.pdfIn PDF document text
    • http://qboardapp.com/wp-content/plugins/super-forms/uploads/php/files/1a977e1e4bf4677e27499b7d3f884d99/furerawujusezoxof.pdfIn PDF document text
    • https://galerie-louise.be/userfiles/files/39267663083.pdfIn PDF document text
    • https://advancedbusiness.co/wp-content/plugins/super-forms/uploads/php/files/cd4568e4e66276634ae8cd2017af1ebc/35606417278.pdfIn PDF document text
    • http://tatagz.com/uploadfile/files/35904367020.pdfIn PDF document text
    • http://ipllaser.in/uploads/37332235788.pdfIn PDF document text
    • http://dansensvenner.dk/imagesfile///23011854605.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=landscape+painting+tutorial+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_off0000d922.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD922 10852 bytes
SHA-256: d7210c54884ac19db210a5de58cf5953005fec934d3f0faaed3f56a00c0fc12d
font_01_sfnt_off0000f220.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF220 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010a32.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A32 18392 bytes
SHA-256: 02bb9286a829b1d095aec13e77470a7f58869897f3e6e33fe3d4cc7862a4f908