Malicious PDF — malware analysis report

Static analysis result for SHA-256 36e1f835368b6e1b…

MALICIOUS

PDF

73.2 KB Created: 2021-06-09 13:02:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-04
MD5: 7e9cdfa308a44c9a02e197eed758d737 SHA-1: 6bb567ba313b3411112e934486877cf2af57ddfd SHA-256: 36e1f835368b6e1b5d3a4cc57993110225364bc14f7f589e71bb46f6cdddc3c3
164 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories and presents a deceptive download button. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://synerhu.ru/uplcv?utm_term=worksheet+on+exponents+and+powers+class+8 PDF link annotation
    • https://www.lenoir-elec.com/wp-content/plugins/super-forms/uploads/php/files/40rpl3d7e8pula0cakja17hdgd/6367983636.pdfIn PDF document text
    • http://grappin-annat-como.com/userfiles/grappin-annat-como.com/file/92545274813.pdfIn PDF document text
    • https://abandassociates.com/ckfinder/userfiles/files/luwetegelax.pdfIn PDF document text
    • https://www.federatedlighting.com/wp-content/plugins/super-forms/uploads/php/files/dd932ded5a6e1e57ab0f03d2dc7f1d2b/koxetototazumupokaki.pdfIn PDF document text
    • https://tripleccompanies.com/wp-content/plugins/super-forms/uploads/php/files/3aaebac1b6faee672d07d2bdcd9ccbc9/44152586861.pdfIn PDF document text
    • https://boldvision.tv/wp-content/plugins/formcraft/file-upload/server/content/files/16076c480dfc98---sudovupofevif.pdfIn PDF document text
    • https://sdyh.gr/wp-content/plugins/super-forms/uploads/php/files/us77qv5cjttsr4u4h8caneptv2/52822700667.pdfIn PDF document text
    • https://hsegroup.ru/wp-content/plugins/super-forms/uploads/php/files/ic1h4hgefavhke81dtpcvobet3/71463647409.pdfIn PDF document text
    • http://schouteninterieurwerk.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160811b880a396---neletoxaxa.pdfIn PDF document text
    • https://pet-fashion.ro/mm/file/12310691498.pdfIn PDF document text
    • http://www.hotel-margherita.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b47e6a8881e---78170901401.pdfIn PDF document text
    • http://feynburg-uhren.de/uploads/sukanapigagumukugeladi.pdfIn PDF document text
    • http://premiumresourcing.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082e2f98153c---23492571304.pdfIn PDF document text
    • https://storage-in-motion.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b2a8f21d1ce---90060823983.pdfIn PDF document text
    • http://bridgesonthepark.com/wp-content/plugins/formcraft/file-upload/server/content/files/160826686363ce---58321837772.pdfIn PDF document text
    • http://training-solutions.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160741d41f3dda---vozeguxuroje.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000df47.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF47 5592 bytes
SHA-256: 41c81ae1e1c416e3b7dfc73480df11cdf1ddcb2d871874bc11dfe01241e1bb06
font_01_sfnt_off0000f261.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF261 10972 bytes
SHA-256: ca923a84fd9f5e949df125301051609921541be39b25242556a4aae131a57e64