Malicious PDF — malware analysis report

Static analysis result for SHA-256 ece483b1278211e9…

MALICIOUS

PDF

108.4 KB Created: 2021-05-29 07:44:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-07
MD5: 7cbf75dd0429fe2b6d4ccc82dc0bc086 SHA-1: efc324b36db3299ce60f280047aa2d5b09dbebb2 SHA-256: ece483b1278211e95baeb4fc51b5bb849733fda0e53d6c8e440445af1e98273a
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file contains a large number of external links pointing to other PDF files hosted on disposable domains, as indicated by the PDF_SEO_LINK_FARM and PDF_SEO_DISPOSABLE_LINK_FARM heuristics. The primary URL, https://mezovuduw.ru/strik?utm_term=c%25C3%25B3digo+de+%25C3%25A9tica+trabajo+social+chile+2019+pdf, suggests a lure related to 'ethics code for social work Chile 2019 PDF'. The ML classifier and ClamAV detection strongly indicate maliciousness, likely related to phishing or malware distribution through this link farm.

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://mezovuduw.ru/strik?utm_term=c%25C3%25B3digo+de+%25C3%25A9tica+trabajo+social+chile+2019+pdf PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4378606/normal_6027b2ed5b9f8.pdfIn PDF document text
    • https://zosolino.weebly.com/uploads/1/3/4/6/134676828/946703.pdfIn PDF document text
    • https://tabawowap.weebly.com/uploads/1/3/4/5/134599755/mojisokigeja_madaditem_riwokeled_texisiwu.pdfIn PDF document text
    • https://tusunupo.weebly.com/uploads/1/3/4/5/134507020/jixokepu.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4426543/normal_5fd1378d45617.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4449771/normal_5fcf445a310dc.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4457011/normal_602c3ca6cb0dd.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4419820/normal_5fd0592f3ad47.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4393900/normal_5fd0d4971d8f3.pdfIn PDF document text
    • https://besunuvoduzusub.weebly.com/uploads/1/3/4/2/134266379/murelejaf.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4376621/normal_605c0037b7ba5.pdfIn PDF document text
    • https://mitegasur.weebly.com/uploads/1/3/1/8/131871816/xabup_dikaken_fexorotipa_rokomi.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4454984/normal_605d94b910dd2.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4452846/normal_5fcdf51f63c22.pdfIn PDF document text
    • https://jomunibudax.weebly.com/uploads/1/3/4/3/134342604/debba1.pdfIn PDF document text
    • https://kukegogefip.weebly.com/uploads/1/3/2/6/132681459/93e36196.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4425533/normal_5ff277ef18568.pdfIn PDF document text
    • https://nijusalelazi.weebly.com/uploads/1/3/4/8/134875584/5caff82acb.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://uploads.strikinglycdn.com/files/ef255807-8a80-4b12-b896-bcd26b8d16dd/sanenelo.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a3d09b2e-12d4-4621-9957-a68d9d6726a6/how_to_get_famous_on_zepeto.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/786d91ce-d7ef-46cc-9576-54c903615472/big_jambox_not_charging.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_off00015874.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15874 6096 bytes
SHA-256: b7a04513c51f16cd03f8d0d0da0fed22875ed867d6dc6cf7b256fce06c48645f
font_01_sfnt_off00016cc1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16CC1 11784 bytes
SHA-256: c56148e167bc03c875bfafc12ccaf76ea980977eb9de67d6d63ff6e78c0a1180
font_02_sfnt_off000192be.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x192BE 4324 bytes
SHA-256: cd94ef65598b1866d0653cdd88243d989fd81359c0e770c2d3a4858f1c2f6d34