Malicious PDF — malware analysis report

Static analysis result for SHA-256 4528ebad0397aca3…

MALICIOUS

PDF

76.3 KB Created: 2021-05-31 09:00:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-22
MD5: c4ef9aeb1c6d48f55b6d6e4ebf4b4e18 SHA-1: 9902e17b97b16f6eb8336815f06dee9ed438436e SHA-256: 4528ebad0397aca3af69c07af72d15c7e9da77742e65f60464cf3cfb65010949
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 0.9991

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://pelibifir.ru/123?utm_term=biomagnification+and+bioaccumulation+pdf PDF link annotation
    • https://roxexiku.weebly.com/uploads/1/3/4/4/134445291/3212311.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4465394/normal_5fea0cb340a40.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4405902/normal_60308b56b2dc4.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4415327/normal_60320b0e54199.pdfIn PDF document text
    • https://fidurelofomus.weebly.com/uploads/1/3/0/7/130740547/1675ec74.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4412890/normal_60008ef8981d1.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4375093/normal_5fd83e4af2dbb.pdfIn PDF document text
    • https://lulitetuxopibol.weebly.com/uploads/1/3/1/1/131164377/4187717.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4393041/normal_60582fb691fcc.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4447089/normal_6056d1281b0fd.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4458407/normal_6045d50964519.pdfIn PDF document text
    • https://toxujubew.weebly.com/uploads/1/3/1/4/131437446/vubopewegupogis.pdfIn PDF document text
    • https://static.s123-cdn-static-d.com/uploads/4481528/normal_60b423c163fee.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4447914/normal_6045eb3ae8c9a.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4403140/normal_605f45b808ccc.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4486552/normal_5fde6cd5cd219.pdfIn PDF document text
    • https://static.s123-cdn-static-d.com/uploads/4417525/normal_60b21fc214461.pdfIn PDF document text
    • https://zosufolukariv.weebly.com/uploads/1/3/4/7/134755865/wosuru.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4367905/normal_602867b29da1e.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/52406197-0945-4108-8881-1e4758b9deae/what_are_the_44_phonetic_sounds.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5d01a055-2219-4ce7-a9a4-5b595bfc0840/2001_dodge_ram_1500_repair_manual_free_download.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8990b102-d919-40df-a7c5-de30bc12b1c7/valuvanasepovowifimitew.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f3b3cbf4-535f-495e-b21b-549997b0ca48/gifemiworekivosuj.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7ab60b8e-3038-418d-a5b8-ac36379ec989/como_nao_morrer_livro.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_off0000ebae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBAE 5388 bytes
SHA-256: e3d5cb73217cf8fc757076704f4911414897b5b08cfd748c9454bd0b7652e798
font_01_sfnt_off0000fdf8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDF8 10948 bytes
SHA-256: d9316b1be66c58d3eaf2b00e171346e12bd3014fee99fc9c8b981de5a139ba91