Malicious PDF — malware analysis report

Static analysis result for SHA-256 8523a8eba38e4282…

MALICIOUS

PDF

80.6 KB Created: 2021-06-11 00:38:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-13
MD5: 237fb55fc9af34fa039af149ce0e633b SHA-1: debd5d36030bcf615b4167d5d34b3fc4679f98e6 SHA-256: 8523a8eba38e42824bba748f0c87bf465582f8e791fcb5c7d22f075b498ac204
186 Risk Score

Malware Insights

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

The PDF contains a significant number of external links, many pointing to disposable hosting services, indicating a link farm or SEO manipulation attempt. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or distributing further malware. No scripts were extracted, but the PDF structure itself is indicative of a malicious lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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://pixomot.ru/pbw?utm_term=kvs+registration+class+1 PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4470532/normal_606e74514c93b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4471945/normal_60103e216fef8.pdfIn PDF document text
    • https://bemakidej.weebly.com/uploads/1/3/0/7/130739127/2076092.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4489615/normal_5fd1d21bcccdb.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4366633/normal_5ffd4e1dc00eb.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4386621/normal_601cdf12d94b1.pdfIn PDF document text
    • https://kukitarigawe.weebly.com/uploads/1/3/0/7/130776277/2306058.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4420013/normal_5fe067e267ec7.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4466153/normal_6032bc356921f.pdfIn PDF document text
    • https://wubajepetodol.weebly.com/uploads/1/3/1/6/131606368/2609796.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4443814/normal_5fd1189e25105.pdfIn PDF document text
    • https://zefijevizo.weebly.com/uploads/1/3/2/3/132302816/buwedosake.pdfIn PDF document text
    • https://jikujumek.weebly.com/uploads/1/3/5/3/135318263/f3d9df7ed3.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
    • http://maxasol.pbworks.com/f/social_club_latest_version_free_download.pdfIn PDF document text
    • http://damopijos.pbworks.com/w/file/fetch/144498267/kemanifeguze.pdfIn PDF document text
    • http://bupataved.pbworks.com/w/file/fetch/144427617/pederiwexogesifinogases.pdfIn PDF document text
    • http://mupalunava.pbworks.com/f/chain_link_fence_installation_price_guide.pdfIn PDF document text
    • http://daridameku.pbworks.com/w/file/fetch/144795735/redemption_accomplished_and_applied_free.pdfIn PDF document text
    • http://gopidam.pbworks.com/f/how_to_download_mspy_app.pdfIn PDF document text
    • http://muzupusap.pbworks.com/f/present_continuous_writing_exercises.pdfIn PDF document text
    • http://xinunubaz.pbworks.com/f/philippine_science_high_school_entrance_exam_reviewer_2020.pdfIn PDF document text
    • http://papoxuva.pbworks.com/w/file/fetch/145054047/dakodagufunimupazoropuj.pdfIn PDF document text
    • http://lakiluxodev.pbworks.com/f/82726006355.pdfIn PDF document text
    • http://degenazi.pbworks.com/f/smart_bracelet_ip67_manual_em_portugues.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f248.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF248 5048 bytes
SHA-256: c44bc17eff7258451ea72fadf0d002b72c2173258c520ada427dc49eea3a79e9
font_01_sfnt_off00010398.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10398 11176 bytes
SHA-256: 38d3803dd63ded2d394b670e295109edec431900a5be55b10d1b387401146d53
font_02_sfnt_off000129c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x129C6 3072 bytes
SHA-256: b4cd0e9292c051e426e97395082e924a6d5aa7c7980009b058c6ce2c3c5fbdc9