Malicious PDF — malware analysis report

Static analysis result for SHA-256 4438f87034990243…

MALICIOUS

PDF

130.9 KB Created: 2021-03-25 04:12:36 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-22
MD5: 67dddd12ae789700d5015eb65c5f0ca7 SHA-1: e90422a0d5989307f6203bf5d84fe2196e7d70d8 SHA-256: 4438f87034990243e29aef65925f9977c9d9e7f379d7c09896cd0f97e7f3b883
252 Risk Score

Malware Insights

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

The PDF contains a large number of embedded links pointing to external PDF files hosted on disposable domains, indicating a link farm. Several heuristics confirm this behavior, including PDF_SEO_LINK_FARM and PDF_SEO_DISPOSABLE_LINK_FARM. The presence of a link to a known malicious redirector further supports the malicious intent. While no scripts were extracted, the overall structure and URL distribution suggest a phishing or SEO manipulation campaign, likely delivered as a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

Heuristics 7

  • 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 links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • 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://dafemum.ru/123?utm_term=sound+booster+app+for+android+mobile In PDF document text
    • http://vkysnaya-eda.site/14266794652qyudm.pdfIn PDF document text
    • https://voganesabif.weebly.com/uploads/1/3/1/1/131163538/e5c47.pdfIn PDF document text
    • https://visimekariluvog.weebly.com/uploads/1/3/1/4/131483525/1069370.pdfIn PDF document text
    • http://bioforce-co.site/siwalelamakobeqznl.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4486552/normal_6028b8682023f.pdfIn PDF document text
    • https://gimexewevojux.weebly.com/uploads/1/3/4/5/134523505/timebakixajut_laxekew_bumimadovawej.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4385422/normal_5fcb797995d65.pdfIn PDF document text
    • https://rifojiditesi.weebly.com/uploads/1/3/1/3/131379396/ludetofulonovegume.pdfIn PDF document text
    • http://zumbayuliya.online/how_to_prepare_for_amazon_intern_interviewszjvj.pdfIn PDF document text
    • https://wigewowatabosaz.weebly.com/uploads/1/3/4/3/134352056/7765981.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4377928/normal_605321c6ed13b.pdfIn PDF document text
    • https://maxawoxemun.weebly.com/uploads/1/3/4/6/134615094/428124.pdfIn PDF document text
    • http://teagreen.space/83312384458wn2vc.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4452609/normal_5fccbd2927793.pdfIn PDF document text
    • https://mowibusox.weebly.com/uploads/1/3/4/5/134591082/mejinasonefemof_lasunemapirak.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4424682/normal_5feba8ef92925.pdfIn PDF document text
    • https://gabejopow.weebly.com/uploads/1/3/4/5/134597712/1cda000c47289.pdfIn PDF document text
    • https://zoxiniguve.weebly.com/uploads/1/3/4/5/134584112/doronuxigo_xoleg_sazakule_bafusadoxufebal.pdfIn PDF document text
    • https://nawivavunof.weebly.com/uploads/1/3/4/6/134669961/nemozutopisifu_pebixawid_mipasi_ratuboposelib.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://e424a478-4e79-4952-a11a-519574c743a8.filesusr.com/ugd/3bcfef_d92fd060b1cd4c2cbccb61a6670486b0.pdf?index=trueIn PDF document text
    • http://giwolexuki.rf.gd/2nd_grade_subtraction_math_worksheets.pdfIn PDF document text
    • https://2ea9429b-0332-4ee6-bb75-ab9535b56c99.filesusr.com/ugd/e2f7e1_3936a7db9c1c4c9ba48cfe4e6f082050.pdf?index=trueIn PDF document text
    • http://pamikope.epizy.com/bangsamoro_basic_law_summary.pdfIn PDF document text
    • http://rawobebisef.epizy.com/56847850170.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_off0001c443.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1C443 5428 bytes
SHA-256: 2a8de5c5776b08b9b59db0992253811f22af9538268b7bd9c0d8564d87ee7d38
font_01_sfnt_off0001d697.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1D697 11832 bytes
SHA-256: 6e5c8459c18fdb1b4585590d58c5c72b2366509fb0d08ae708e7dc7cec9ae410