Malicious PDF — malware analysis report

Static analysis result for SHA-256 c1408209d4da302b…

MALICIOUS

PDF

73.3 KB Created: 2021-10-09 20:13:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 4f66168fbadab4ee2f31bfa0d254de8d SHA-1: 2507f01aa14ef2a0e3b22091a70014c11c3347ad SHA-256: c1408209d4da302b39b180a1a668a0f3473bb399ebc26cd247c6931af3043e0d
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was identified as malicious by ClamAV and an ML classifier, with heuristics indicating embedded JavaScript and a link farm structure. The embedded JavaScript likely facilitates the redirection to a collection of external PDF files hosted on various domains, suggesting a phishing or malware distribution campaign. The presence of numerous links and the link farm heuristic point towards an attempt to obscure the true malicious destination or to host a large number of lures.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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
  • 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 http://arabic.cz/ckfinder/userfiles/files/rotazatarofanagusarukuvo.pdf In PDF document text
    • https://xn--23-6kci4asohe8k.xn--p1ai/userfiles/file/wuxezajerixokusibukobajup.pdfIn PDF document text
    • http://www.aamuhsv-madisonalumni.org/files/files/13384807262.pdfIn PDF document text
    • http://szentdorottyapatika.hu/files/39931817403.pdfIn PDF document text
    • https://www.iieng.org/editor/ckfinder/userfiles/files/bixora.pdfIn PDF document text
    • http://cavusofis.com/images_upload/files/guxevonadiwugukime.pdfIn PDF document text
    • https://handinhand-daycare.com/ckfinder/userfiles/files/13240008984.pdfIn PDF document text
    • http://boletos.luzservicos.com/ckfinder/userfiles/files/zuwirurepigalesowu.pdfIn PDF document text
    • http://tokyoracing.hu/userfiles/file/56709824867.pdfIn PDF document text
    • http://closehorses.com/userfiles/file/sujoxusifavajanonofuri.pdfIn PDF document text
    • http://fazendasaojudastadeu.net/fotosempresa/files/nuwazugukotanatad.pdfIn PDF document text
    • http://sineadstone.com/userfiles/file/95838585970.pdfIn PDF document text
    • http://www.leads-bd.org/app/webroot/js/ckfinder/userfiles/files/71015147941.pdfIn PDF document text
    • http://airmon.hu/images/files/kebixubotomaxaw.pdfIn PDF document text
    • http://isystem.hu/userfiles/file/zomuwezowaguxelu.pdfIn PDF document text
    • http://mmbassisiprovince.in/files/js/ckfinder/userfiles/files/tamudiwopudusetikutikevez.pdfIn PDF document text
    • http://biomax.shop/filespath/files/20210926003438.pdfIn PDF document text
    • http://www.peritaonline.es/ckfinder/userfiles/files/vuzip.pdfIn PDF document text
    • https://www.sir.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/161443bdfa9f8c---71726626094.pdfIn PDF document text
    • http://www.jindatunnel.com/up_files/file/tivuvinubiderovasamodif.pdfIn PDF document text
    • http://nakakinpump.kr/fckeditor/upload/file/79540574216.pdfIn PDF document text
    • http://ingegnasrl.com/userfiles/files/lapebujikigifaloloxo.pdfIn PDF document text
    • http://www.advokat.com/app/webroot/img/fck/file/fadijikusuna.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=my+time+at+portia+street+lightPDF 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_off0000be50.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBE50 15852 bytes
SHA-256: 5c4857d610262db527a2299f494f8954c06cde4640af712a9b0c554c410aa24c
font_01_sfnt_off0000e6b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6B0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000fec7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFEC7 10704 bytes
SHA-256: 23b7988df72bfd55108d1c0371a1c3a27d52e2359ca248b1424561a5812e53d2