Malicious PDF — malware analysis report

Static analysis result for SHA-256 3357a8f4b5bb2d46…

MALICIOUS

PDF

72.1 KB Created: 2021-09-18 07:53:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: a4d3596f8e0e4b2b3a2ec916d4a2106f SHA-1: 6464d8e612d0978f55dffecd09b087a75cfc8242 SHA-256: 3357a8f4b5bb2d46ae67f1806f86b5c81e6e2ce003c7ea8c1ab17b882898b0ff
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and a significant number of external URIs, many of which are hosted on compromised WordPress sites or disposable domains, indicating a link farm for phishing or malware distribution. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or trojan delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://rajaketiga.com/contents/files/42882551455.pdf In PDF document text
    • http://champaigncursillo.com/userfiles/file/lidokuxonaruv.pdfIn PDF document text
    • http://cuborh.com/natelinhanew/js/ckfinder/userfiles/files/zoraxaborugis.pdfIn PDF document text
    • http://www.dnevi-sekretarjev.eu/wp-content/plugins/formcraft/file-upload/server/content/files/16141639b62f77---ritokuvaxivojofapuwaxol.pdfIn PDF document text
    • http://wwm-quanta.com/upload/files/davadasexoru.pdfIn PDF document text
    • http://eminenceinc.com/userfiles/file/zemitugafatas.pdfIn PDF document text
    • https://ladulceseguros.ar/noticias/fckeditor/file/zimogetut.pdfIn PDF document text
    • http://uitvaartverzorgingsindex.nl/images/uploads/34637446452.pdfIn PDF document text
    • https://itchanoi.vn/uploads/news_file/jolixo.pdfIn PDF document text
    • http://audiomaster.se/wp-content/plugins/formcraft/file-upload/server/content/files/16140136f87a19---50848651180.pdfIn PDF document text
    • http://xn----7sbndn5at.xn--p1ai/uploads/files/xalexiwapojofogabezinov.pdfIn PDF document text
    • https://shinaltd.ru/images/file/20594524339.pdfIn PDF document text
    • https://www.ocnistudio.cz/ckfinder/userfiles/files/89627119547.pdfIn PDF document text
    • https://www.novet.de/wp-content/plugins/formcraft/file-upload/server/content/files/16137e2734f91d---44941537090.pdfIn PDF document text
    • http://kortennis.co.kr/B/ck/ckfinder/userfiles/files/wobiwa.pdfIn PDF document text
    • http://hflchw.com/upload/file/mirigaworubas.pdfIn PDF document text
    • https://tezerwatch.com/file/upload/files/09-17-04-27-31-24.pdfIn PDF document text
    • https://onlinendttraining.com/files/57543158199.pdfIn PDF document text
    • http://islaminkiel.de/webmisr/uploadwebmisr/file/81907178003.pdfIn PDF document text
    • https://phuquiland.com/upload/files/redake.pdfIn PDF document text
    • http://stfurnimart.com/file_media/file_image/file/suwuluviselitufixejuju.pdfIn PDF document text
    • https://butchercurnow.com/img/shop/contents/83011416436.pdfIn PDF document text
    • http://quesnelbusinessnetwork.ca/userfiles/file/navazetadomikuxufuviwofa.pdfIn PDF document text
    • http://files.ibiza-ferien.de/file/13274020439.pdfIn PDF document text
    • https://hoffmanowska.pl/wp-content/plugins/formcraft/file-upload/server/content/files/161406fcf3edae---lefipekexuwup.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=doomed+2+ioPDF 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_off0000b365.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB365 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cb7b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB7B 9852 bytes
SHA-256: 3345d47ffd661ae47c93bc0491e74208bbfcc9e85f5f63c9b8e5db83a5d29c63
font_02_sfnt_off0000e11f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE11F 19840 bytes
SHA-256: 240021c8f022f120a9b7493050c75cd558787cb8268d1ce788910dfa0a17c33a