Malicious PDF — malware analysis report

Static analysis result for SHA-256 04a0f3c59b74af67…

MALICIOUS

PDF

79.8 KB Created: 2021-09-12 16:57:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 97dcd80e4b3e9d0856f1a787cf2ee595 SHA-1: f4c277b95178517b96a06e04f8187996ae87a7da SHA-256: 04a0f3c59b74af67867f8dba8608de4d48c392f3de5deaee12c3e67d151e7dd7
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many pointing to compromised or disposable hosting, indicative of a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or malware distribution. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' confirms the presence of a link farm on disposable hosting, with one URL specifically mentioning 'open a pdf without password' as a utm_term, suggesting a lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://coretry.ru/uplcv?utm_term=open+a+pdf+without+password PDF link annotation
    • http://www.c-l-r-p.com/admin/ckfinder/userfiles/files/zuxarekisibukixedak.pdfIn PDF document text
    • http://levotst.com/uploads/files/xokonotapa.pdfIn PDF document text
    • http://nuklearmedizin-amro.de/userfiles/file/zufiwap.pdfIn PDF document text
    • http://abcbyspu.com/ckfinder/images_store/files/wimikuvopivun.pdfIn PDF document text
    • http://auswallendorf.de/userfiles/file/koraxolik.pdfIn PDF document text
    • https://tspinstruments.com/cache/fck_files/file/29858310226.pdfIn PDF document text
    • https://kvartira-zalog.ru/wp-content/plugins/super-forms/uploads/php/files/6399dadda9aca38d1dd81041c92fd720/80547654939.pdfIn PDF document text
    • https://nusamulticentralestari.com/Uploads/userfiles/files/lukiwosuredatujugapaje.pdfIn PDF document text
    • http://www.superior-inkjet.com/login/ckfinder/userfiles/files/witadonodiwi.pdfIn PDF document text
    • http://www.icodar.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d2966ce796---bojaravadezif.pdfIn PDF document text
    • https://xn--64-mlcufjjaii0l.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/14f460560e23aaf0eb7e574d4f671ca1/54757740969.pdfIn PDF document text
    • https://www.lesson-online.org/wp-content/plugins/super-forms/uploads/php/files/gbpsu5vpqesjepdj5dhjtf93k5/jobonewulaxegase.pdfIn PDF document text
    • https://www.playitdirect.ca/ckfinder/uploadfiles/files/wukirasinuro.pdfIn PDF document text
    • https://rewaqousha.net/userfiles/files/2431722312.pdfIn PDF document text
    • http://wwsm-us.com/files/file/25341302385.pdfIn PDF document text
    • http://xn--h49al71atridzo.com/userData/board/file/21387559766.pdfIn PDF document text
    • http://gemcom.org/userfiles/file/mosigagiroladix.pdfIn PDF document text
    • https://santa.sg/images/users/00000000/files/bijenodewirutuxirusumu.pdfIn PDF document text
    • https://alhurwallpaper.com/Files/files/52274959776.pdfIn PDF document text
    • http://zawodydrwali.pl/app/webroot/userfiles/file/55268073548.pdfIn PDF document text
    • https://lapdonline.org/file/fedakeji.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_off0000d4c4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD4C4 17064 bytes
SHA-256: 0a673e4b6404fdd8a287c3c72893cf31516c234d19e8fa9bd65c9acda76dab7f
font_01_sfnt_off000100b7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100B7 10760 bytes
SHA-256: ebbb5910066b3db74fcb355d98368af8d2147f40f0b2dcee0dc38f1c4bbdfa72
font_02_sfnt_off00011981.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11981 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1