Malicious PDF — malware analysis report

Static analysis result for SHA-256 83b95576fb1615db…

MALICIOUS

PDF

70.4 KB Created: 2021-09-25 11:15:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: c99b56d1b292b44b1e15c8a4a0bf1de3 SHA-1: 7b2b35bd5d548ada1cadb055873236f5772ee8ff SHA-256: 83b95576fb1615db14d43e516bb27ea406aa8a9b7527b9e274e482d2f7f11b24
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate the PDF contains a link farm with numerous URLs, many hosted on potentially compromised or disposable domains. These links likely serve as a lure to redirect users to malicious content, aligning with a phishing or content-abuse attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9908

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://hrudolf.com/userfiles/96193712672.pdf In PDF document text
    • http://shengnabei.com/uploadfile/file///2021090901101852.pdfIn PDF document text
    • https://antoinepanau.com/wp-content/plugins/super-forms/uploads/php/files/f8bc95bc04cd3994f91403dd333c7187/8593887112.pdfIn PDF document text
    • http://vimar.ua/userfiles/files/muwewilonuduvunobopuzed.pdfIn PDF document text
    • https://laxmigrouppune.com/wp-content/plugins/super-forms/uploads/php/files/1d228709d45a0e851eb7e38ea7570b18/97596418051.pdfIn PDF document text
    • http://studiodebiaggi.eu/userfiles/files/94665172879.pdfIn PDF document text
    • http://tea-ra.com/user_data/upload/save_image/files/66682754786.pdfIn PDF document text
    • http://zoekidsworld.com/userfiles/file/16259624649.pdfIn PDF document text
    • http://tweddlefoto.com/files_contenidos/upload/files/51555034636.pdfIn PDF document text
    • http://tcsklife.com/filespath/files/20210910153343.pdfIn PDF document text
    • http://hansungidschool.com/userfiles/file/75100654904.pdfIn PDF document text
    • https://edinburghpools.com/contents/files/50275752757.pdfIn PDF document text
    • http://flex-link.cn/uploadfiles/files/zagememijok.pdfIn PDF document text
    • https://csn-alliance.com/data/files/kajatukozutinog.pdfIn PDF document text
    • https://hizlipin.com/calisma2/files/uploads/livatodimiva.pdfIn PDF document text
    • http://jedzenie365.pl/ckfinder/userfiles/files/40666433810.pdfIn PDF document text
    • http://huarong-bio.com/upload/files/2015155342.pdfIn PDF document text
    • http://rdasesores.gestconcursal.com/editor/ckfinder/userfiles/files/35709957888.pdfIn PDF document text
    • http://em-ail.ch/pictures/2/43594568560.pdfIn PDF document text
    • https://shevtsov-art.com/uploads/files/58062860511.pdfIn PDF document text
    • https://polytex.de/sites/default/files/detelevafijubi.pdfIn PDF document text
    • https://atlasautoglass.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612eac8a00293---kebezepufalo.pdfIn PDF document text
    • http://damosushipleasanthill.com/uploads/files/lapurunatorubog.pdfIn PDF document text
    • https://jeevandeepspecialcare.com/ckeditor/ckfinder/userfiles/files/69761762623.pdfIn PDF document text
    • https://deitratech.com/userfiles/file/17725580173.pdfIn PDF document text
    • http://dogalakustik.com/depo/sayfaresim/file/30915792240.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=final+fantasy+legend+iii+romPDF 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_off0000b43c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB43C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cc53.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC53 10788 bytes
SHA-256: 6908c38d581c1229e76dd092f1f6f0fa7549e9c5c3035ac92e2a21d48d4ace33
font_02_sfnt_off0000e4f0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4F0 14628 bytes
SHA-256: 5a1b52b9fab5f150d66123aa4ec3009ce2b92e35d50d34b065d4e42e228dc712