Malicious PDF — malware analysis report

Static analysis result for SHA-256 db455a11c7787c5b…

MALICIOUS

PDF

65.8 KB Created: 2021-06-23 15:47:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-07
MD5: f2b3a28a0699c9a0ae3c418975eca7cf SHA-1: b269ae8b837ddf7268ae5cf6a7d55f29d510bdfd SHA-256: db455a11c7787c5b60855bb3c7724ba40b4626762a8ce3c431c2340fea804703
156 Risk Score

Malware Insights

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

The PDF contains a link farm hosted on multiple compromised WordPress sites, indicating a phishing or redirection attempt. The ML classifier and ClamAV detection strongly suggest malicious intent, likely to lead users to malicious content or further stages of an attack. No scripts were extracted, but the presence of numerous URLs on compromised domains is a high-confidence indicator of malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://china-engine.net/ckfinder/userfiles/files/levokonu.pdf In PDF document text
    • https://xn--80aaaglcftt5alesfkk7f.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/89be2dec3e1cf68d65e0bbab80171ae4/63761333466.pdfIn PDF document text
    • http://przychodnia-felinskiego.pl/uploads/editor/file/libureledupejuveropev.pdfIn PDF document text
    • http://stopasbestos.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16098a9cf59f30---67321270552.pdfIn PDF document text
    • https://gfow.om/wp-content/plugins/super-forms/uploads/php/files/jklf6gj72lqs6f5m24o1eocrlj/nubozurevabepuwufomaxisi.pdfIn PDF document text
    • http://www.tomasjelinek.com/img/pub/file/vumifogada.pdfIn PDF document text
    • https://postelezmasivu-ostrava.cz/ckfinder/userfiles/files/31027540958.pdfIn PDF document text
    • https://www.enterpriselighting.com/wp-content/plugins/super-forms/uploads/php/files/94010cdfc87cf055fc7c02ebd8a50f2d/23059835788.pdfIn PDF document text
    • http://mirandatutoringcentre.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1607059dd27a8c---pozanixuzinaxulotojovoz.pdfIn PDF document text
    • https://maxim-catering.de/wp-content/plugins/super-forms/uploads/php/files/885iru25pm0qr7navk87el6qek/3133495008.pdfIn PDF document text
    • http://www.theagentpipeline.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072f944127ae---kodulotupudoxaviruzipive.pdfIn PDF document text
    • https://elicopter-de-inchiriat.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1608b5fa775db1---23681232406.pdfIn PDF document text
    • http://asesorialuishervas.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079ab38cd6a8---70374885919.pdfIn PDF document text
    • https://wurstfargo.com/wp-content/plugins/super-forms/uploads/php/files/8077289213e762d298677090182709af/78503362712.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://fedorahosted.org/lohitIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=picture+comprehension+for+class+4PDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b8ae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB8AE 5344 bytes
SHA-256: a477b9cd5089ef26c8a49deacb3d870a2b3287ddeeff0770f619454d0fd3fc7d
font_01_sfnt_off0000cab6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCAB6 9136 bytes
SHA-256: 2ae772da327da09cfaa8f3f23ddaca7fc57b75179b81420a5d388d78290178c8
font_02_sfnt_off0000e9d4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9D4 4500 bytes
SHA-256: ac9174a588544edbcaef1e095eb5dd45644a4a333857b4a5006e7b738a33567b