Malicious PDF — malware analysis report

Static analysis result for SHA-256 f440e40ae1b19d82…

MALICIOUS

PDF

94.6 KB Created: 2021-09-13 00:58:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 45d84f417f9e7d6d308967bbdb3952a7 SHA-1: a587e6b3c61df877c47ed00170ab73e9c58aaf15 SHA-256: f440e40ae1b19d82628fbddc03297135c4bcb49aaa5a083ef4c4f4fd899c33fc
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to compromised CMS upload directories or are part of a link farm hosted on disposable domains. The primary purpose appears to be directing users to external, potentially malicious, websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9935

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://olterus.info/contents/files/zekenaxuwelorafuza.pdf In PDF document text
    • http://parmalab.it/userfiles/files/zejuwefasisopobof.pdfIn PDF document text
    • http://mamitobe.ru/files/file/66847030012.pdfIn PDF document text
    • http://getampedmag.com/ckfinder/userfiles/files/sewesunosa.pdfIn PDF document text
    • https://vanphongphampmc.com/upload/files/digiwasof.pdfIn PDF document text
    • https://lexcyberia.com/userfiles/files/vuruxawuvebirir.pdfIn PDF document text
    • https://cytokin.ca/upload/editor/file/gefadaxanimikobasubegizen.pdfIn PDF document text
    • https://kanat.com/upload/ckfinder/files/kewedotusefasari.pdfIn PDF document text
    • https://granitnet.hu/editor_up/10406702922.pdfIn PDF document text
    • https://heart-calligraphy.com/uploads/files/202109070300306019.pdfIn PDF document text
    • http://www.gc-antey.ru/ckfinder/userfiles/files/73718508128.pdfIn PDF document text
    • http://rheumatology.institute/upload/content/file/66080032760.pdfIn PDF document text
    • http://fishtech.org/uploads/userfiles/file/file/witabimitejepasidigegox.pdfIn PDF document text
    • http://tyros-club.de/userfiles/file/54001532357.pdfIn PDF document text
    • http://beckydavidsonhomes.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613031e314628---rodeganasolawejotifixapam.pdfIn PDF document text
    • http://boletos.luzservicos.com/ckfinder/userfiles/files/34989137457.pdfIn PDF document text
    • https://balticstroy.com/uploads/files/legusogoxowapanemozi.pdfIn PDF document text
    • http://ttmplus.com/userfiles/files/32579256993.pdfIn PDF document text
    • http://amtusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f02b695c8d---21544337003.pdfIn PDF document text
    • https://actaviaserica.org/board/file/files/82708809279.pdfIn PDF document text
    • https://stomatoloska-ordinacija-rijeka.com/files/91959818441.pdfIn PDF document text
    • http://mfcpavpos.ru/file/49153584092.pdfIn PDF document text
    • http://cz-synergy.cz/data/file/52147308899.pdfIn PDF document text
    • http://www.fliesen-brill.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613c03a407af3---14118198855.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=instagram+followers+for+free+2020PDF 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_off00010c43.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C43 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00012455.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12455 18416 bytes
SHA-256: 14387c7dce5feeec8dc3edbcd6d80ea0bbe566dfff4703618c8a39bf43b0f071
font_02_sfnt_off00015447.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15447 10744 bytes
SHA-256: f4ea9d3290ef2201f8b4374bbc10c17f072bc601dbabee8a1e8559d48eb4ecdc