Malicious PDF — malware analysis report

Static analysis result for SHA-256 a8fda4304da97a20…

MALICIOUS

PDF

83.5 KB Created: 2021-09-08 04:11:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: ae8a465420016fa09d9c8e7c73829afb SHA-1: 0c2434d8429eb907c5e21fddec3f7f1d929e27a7 SHA-256: a8fda4304da97a2036e1830a3d81edd66b44126521a1e47a5788bb7f0d4af59d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Numerous URLs were extracted, many pointing to compromised websites or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics further supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://krisoc.ru/uplcv?utm_term=electrotechnics+basics+pdf PDF link annotation
    • http://budohurtsa.pl/userfiles/file/ziporurufol.pdfIn PDF document text
    • http://stellamaris.cz/userfiles/65542223740.pdfIn PDF document text
    • http://alemotta.com/resources/original/file/kopisumexupagilexuvi.pdfIn PDF document text
    • http://avatars.ru/userfiles/file/wigerusawazujilibijasuda.pdfIn PDF document text
    • http://htwy.com/upload/file/lipaloleke.pdfIn PDF document text
    • http://sonnenheizungen.ch/fckeditor/editor/images/file/6900388457.pdfIn PDF document text
    • http://www.belladermeestetica.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16082b6b429557---67760306352.pdfIn PDF document text
    • http://alvasari.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d64e91561ef---41238952308.pdfIn PDF document text
    • https://jyapa.com/jhuoyue/uploadfiles/zegejir.pdfIn PDF document text
    • https://gpuhub.net/wp-content/plugins/super-forms/uploads/php/files/ik4pinadl1shnio5tm9tka8g7b/12329497258.pdfIn PDF document text
    • http://fuku-zou.com/userfiles/file/fewovufamugadu.pdfIn PDF document text
    • http://dansecyr.ca/pdf/file/selotidirupexenobexogi.pdfIn PDF document text
    • https://husvagnsexpo.se/wp-content/plugins/formcraft/file-upload/server/content/files/1609e2e254ad90---48085350403.pdfIn PDF document text
    • https://medok18.ru/wp-content/plugins/super-forms/uploads/php/files/014036467d2fee636b9c229e4f3c70b0/nobibudu.pdfIn PDF document text
    • http://sanders-scottfamily.com/clients/26926/File/vabonaxavine.pdfIn PDF document text
    • https://igk-lilienthal.de/downloads/gupipituvovijatof.pdfIn PDF document text
    • http://greenbrier101.com/userimages/51707810099.pdfIn PDF document text
    • https://ekransamara.ru/files/13517788390.pdfIn PDF document text
    • http://asalsold.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a637d900737---25655151498.pdfIn PDF document text
    • http://www.kmclogistics.com/wp-content/plugins/super-forms/uploads/php/files/fc8024ced4e5e4a28a0b947e572a8e8a/67627289441.pdfIn PDF document text
    • https://burkina-businessschool.com/business_school/uploads/file/69005403764.pdfIn PDF document text
    • http://kino-cosmik.ru/sadm_files/gimoxijibowor.pdfIn PDF document text
    • http://onelove.cz/file/88952011602.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_off0000e05c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE05C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f86e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF86E 18064 bytes
SHA-256: fbd8ca2c251b7c9a0cf598203bcbf2d8b01120c23bf02e6678dbe53c2c85a0b2
font_02_sfnt_off000127e0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x127E0 10840 bytes
SHA-256: 299d2b85a5e783ab5b0a3ec9f817c49d6691b40f71702b7f4b8213df4eb34497

Open this report in the interactive analyzer, or submit your own file for analysis.