Malicious PDF — malware analysis report

Static analysis result for SHA-256 71b4c873193ec5ad…

MALICIOUS

PDF

76.8 KB Created: 2021-06-01 11:52:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-01
MD5: 4b4428f18b89c07bcc335f750ac29b5b SHA-1: 72dfae0af123259fdf41ed1e0d3fa69de78aa022 SHA-256: 71b4c873193ec5ad0ff0761d2642946d65a7088d7f9c1b1b414daa49fc7da139
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

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. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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 contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • 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://pistant.ru/pbw?utm_term=sat+math+no+calculator+practice+pdf PDF link annotation
    • https://gewuzonaxos.weebly.com/uploads/1/3/4/7/134714103/pavinusozibizijo.pdfIn PDF document text
    • https://xakirajurupani.weebly.com/uploads/1/3/2/3/132303083/lenejuso.pdfIn PDF document text
    • https://kiwuvewe.weebly.com/uploads/1/3/7/5/137509443/8492616.pdfIn PDF document text
    • https://zoziwaxixu.weebly.com/uploads/1/3/5/3/135316133/pevuverig_mifor.pdfIn PDF document text
    • https://lewofadexireg.weebly.com/uploads/1/3/4/8/134868993/xinomekum.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4491969/normal_601db4b3839cc.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4477137/normal_606318e2082c0.pdfIn PDF document text
    • https://nasaxedinevizuv.weebly.com/uploads/1/3/4/7/134759800/2469e3.pdfIn PDF document text
    • https://static.s123-cdn-static-d.com/uploads/4501660/normal_60b3f559211ba.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4476294/normal_60062c5f9a5e8.pdfIn PDF document text
    • https://penabapemuzoji.weebly.com/uploads/1/3/1/4/131453208/f5c89854b8bf2.pdfIn PDF document text
    • https://kizegugiruliti.weebly.com/uploads/1/3/4/7/134729255/nifatuxiniwipilexoj.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4411691/normal_5fcebed9974de.pdfIn PDF document text
    • https://xijogokamu.weebly.com/uploads/1/3/4/7/134721509/kuxofeneb.pdfIn PDF document text
    • https://kimonasisu.weebly.com/uploads/1/3/5/4/135400987/jizipakipanowozil.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4373776/normal_60594d5479aae.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4378164/normal_5ff9fbd2d37d4.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://bojirakaj.pbworks.com/f/1176114755.pdfIn PDF document text
    • http://kipizasuzeda.pbworks.com/f/69762398152.pdfIn PDF document text
    • http://pevozowo.pbworks.com/f/ronevuxamejumesuzage.pdfIn PDF document text
    • http://rugewenuzed.pbworks.com/f/the_great_american_songbook_the_composers.pdfIn PDF document text
    • http://fipivuzigoge.pbworks.com/w/file/fetch/144424524/cuales_son_los_tipos_de_sistemas_operativos_mas_comunes.pdfIn PDF document text
    • http://gitefov.pbworks.com/w/file/fetch/144452817/tawikagekojimumibola.pdfIn PDF document text
    • http://zuvevetub.pbworks.com/w/file/fetch/144421527/calibri_bold_font_free_download_mac_os_x.pdfIn PDF document text
    • http://buvavipoluvu.pbworks.com/w/file/fetch/144424998/iso_interested_parties_template.pdfIn PDF document text
    • http://wijozuzapusa.pbworks.com/f/95878385142.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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ef3b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF3B 5320 bytes
SHA-256: 935f432117befe47d7a7afc6403c3e271b7bc98dbd3b1e899e644c4398196b4d
font_01_sfnt_off00010127.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10127 10696 bytes
SHA-256: aa853864b96394730c486a8abc6684f6b0842ea04b7938e5274bdf1a4adbcc24