Malicious PDF — malware analysis report

Static analysis result for SHA-256 b1f87a41e0491ab4…

MALICIOUS

PDF

78.9 KB Created: 2021-03-11 17:37:25 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-25
MD5: 083ec97c9cfd140eaa4a7c338ed5b70c SHA-1: dc8992c6263ecaf776709e354a2ad8c56ecb1fb3 SHA-256: b1f87a41e0491ab425530b7d0964ab554a4c7ba76a1e738b3df817de84154143
186 Risk Score

Malware Insights

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

This PDF file was identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It contains a large number of external links, many pointing to disposable hosting, suggesting a link farm designed to drive traffic or host malicious content. The document body is heavily obfuscated and unreadable, but the presence of numerous external links and the heuristic firings strongly indicate a malicious intent to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://maypoin.ru/award?keyword=core+java+interview+questions+pdf+javatpoint PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4450734/normal_60161d0cee896.pdfIn PDF document text
    • https://zafasasuk.weebly.com/uploads/1/3/4/7/134713251/fudidolimalav.pdfIn PDF document text
    • https://xojobade.weebly.com/uploads/1/3/4/3/134385351/feraxe.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4477167/normal_5fd1f142a3a74.pdfIn PDF document text
    • http://motawosofi.iblogger.org/ferarizazalitid.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4491439/normal_5ff7c328ddc87.pdfIn PDF document text
    • http://fovuvizoge.22web.org/holomorphic_function_definition.pdfIn PDF document text
    • https://depasosuva.weebly.com/uploads/1/3/4/4/134483816/zawonipo.pdfIn PDF document text
    • https://xekuruwagimutuz.weebly.com/uploads/1/3/2/6/132696141/af8f5300.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4391907/normal_6003efc9117c6.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4367275/normal_5feb40516aa7e.pdfIn PDF document text
    • https://gekonoxare.weebly.com/uploads/1/3/4/4/134480638/gagilebivipadik-mawuwitapifej-bemufudepi-kevuni.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4502833/normal_6024a657ba92b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4476146/normal_601ddb1cdffe1.pdfIn PDF document text
    • https://damemerivojed.weebly.com/uploads/1/3/4/3/134378109/2493528.pdfIn PDF document text
    • https://fojomuku.weebly.com/uploads/1/3/4/4/134447263/wokibukavodukar_gutakavu_xelevofeliv.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4377717/normal_60257f63e7007.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4402707/normal_603c65f8c0514.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://b9eb3541-094c-4606-b101-17c2291fd6e1.filesusr.com/ugd/a18601_4092616e17004d0abdb4fa4a056eca93.pdf?index=trueIn PDF document text
    • https://507d1b22-ea03-4061-a262-f79425337ca2.filesusr.com/ugd/a374b9_c90f069912c649b49a22aacf059beeb4.pdf?index=trueIn PDF document text
    • http://fopuzotetowux.rf.gd/51698739689.pdfIn PDF document text
    • http://koxogulu.rf.gd/hydraulic_oil_iso_46_datasheet.pdfIn PDF document text
    • https://64e18f06-8a0e-4dc1-8427-9dd81b4bff36.filesusr.com/ugd/baa514_afb2ad4fe4de43269365f964d955d47a.pdf?index=trueIn 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_off0000f87c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF87C 5260 bytes
SHA-256: 3f7bc95461cb54b2075f6975f43b965520568362bbe39b9cc660aff2a5522fa6
font_01_sfnt_off00010a83.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A83 10376 bytes
SHA-256: d7282ca6fd41c31ad3d2925505b364ff01d34a961f3a6e1d6665baba0b228c79