Malicious PDF — malware analysis report

Static analysis result for SHA-256 1003aa6b3d345880…

MALICIOUS

PDF

75.8 KB Created: 2021-08-28 03:16:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 0d029a3363661363fe124b5a8a229c34 SHA-1: c0ccd16e11104d717cf6307a5abf41c2477e2903 SHA-256: 1003aa6b3d345880ff7b9fe7db676014a47b544bc278b36b8173eda18a9608dc
156 Risk Score

Malware Insights

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

The sample is identified as malicious by ML classifiers and ClamAV, specifically as a phishing trojan. It functions as a link farm, with numerous embedded URLs pointing to compromised CMS uploads and disposable hosting, suggesting an attempt to redirect users to malicious sites. While no scripts were explicitly extracted, the PDF structure and embedded links are indicative of a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://nadiadsa.org/userfiles/file/71104491748.pdf In PDF document text
    • https://greenlakepaint.com/ckfinder/userfiles/files/41594027462.pdfIn PDF document text
    • http://www.look4job.gr/images/_user_na/file/74048532426.pdfIn PDF document text
    • https://medius.sk/userfiles/file/2409360053.pdfIn PDF document text
    • http://sieuthivatlieuhoanthien.com/upload/files/4879475298.pdfIn PDF document text
    • https://www.geya99.com/ckfinder/userfiles/files/84875224811.pdfIn PDF document text
    • http://aodaiminhhanh.com/app/webroot/uploads/files/donunodexi.pdfIn PDF document text
    • https://stef-nancy.fr/upload/document/vomarorezilezeloni.pdfIn PDF document text
    • http://www.moyekolodin.com/files/43166718221.pdfIn PDF document text
    • https://msr-hudsonproperties.com/wp-content/plugins/super-forms/uploads/php/files/6740b2282a26afb64a96de7c20b6f081/rabigeluvu.pdfIn PDF document text
    • https://storage-in-motion.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a31cedb449e---60926427233.pdfIn PDF document text
    • http://cetinelektrik.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16077c1c0d803a---70863769626.pdfIn PDF document text
    • http://dom-nenilovo.ru/wp-content/plugins/super-forms/uploads/php/files/b758215251115452b9874da6b2882046/59151338523.pdfIn PDF document text
    • https://big-cash.de/wp-content/plugins/super-forms/uploads/php/files/vq38dhbtspnpa0vk9tju6m50ld/44449637513.pdfIn PDF document text
    • https://mavismanagement.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b1724a9ded7---5923821651.pdfIn PDF document text
    • http://surtek.biz/image/files/20150104_132559.pdfIn PDF document text
    • https://resicolor.com/upload/files/61479174537.pdfIn PDF document text
    • http://agriturismolataggiasca.eu/userfiles/files/lebaraseva.pdfIn PDF document text
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607ba27eba71f---botuxonup.pdfIn PDF document text
    • https://patriot.ch/wp-content/plugins/super-forms/uploads/php/files/5d6o6pq8b5fbkr4ivefidtc8r9/13183168713.pdfIn PDF document text
    • http://htwy.com/upload/file/8641733771.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b0df2d1a64b---milimi.pdfIn PDF document text
    • http://ontsgoi.shop/uploads/files/72187026183.pdfIn PDF document text
    • http://acmemask.com/upfiles/editor/files/dixubuzu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=how+to+unblock+friend+in+pubgPDF 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_off0000c44b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC44B 16528 bytes
SHA-256: ae2f199a4a3a350ea7646eddf0cfa90bc80c781c4da7c5bff9bc8971ca9a5517
font_01_sfnt_off0000eec6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEC6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000106dd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106DD 10872 bytes
SHA-256: bf2ebb990c172201271fa247fd092ccd5c0940c1a271aa09a1efcdf049bb7380