Malicious PDF — malware analysis report

Static analysis result for SHA-256 bf99375e844b347a…

MALICIOUS

PDF

82.6 KB Created: 2021-04-29 22:19:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-23
MD5: 20d00527192ac64b316c464a137efdb8 SHA-1: 23ae9b756ab53a10700a068740c5dbc43025ebc8 SHA-256: bf99375e844b347ac09e7ac45ad5da27dbd255bd654dc4e071462d6a1244aefd
186 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, a technique often used for SEO manipulation or to redirect users to malicious sites. The ClamAV detection and ML classifier strongly indicate malicious intent, specifically identified as a phishing trojan. While no scripts were directly extracted, the PDF structure and embedded URLs suggest an attempt to lead users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://botokaw.ru/strik?utm_term=what+is+the+best+stock+market+to+buy+in+gta+5 PDF link annotation
    • https://sowobufujugazid.weebly.com/uploads/1/3/0/8/130873997/aecc309ff4a11.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4417808/normal_60667f9939939.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4499958/normal_5fd7f4d663ee5.pdfIn PDF document text
    • https://dimegowogox.weebly.com/uploads/1/3/3/9/133999821/4854824.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4450746/normal_606e20db854c2.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4374847/normal_605066f1c25da.pdfIn PDF document text
    • https://guxemufisi.weebly.com/uploads/1/3/2/7/132710659/faxiv.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4401982/normal_5fcc94d8c5974.pdfIn PDF document text
    • http://nokojatagi.mywebcommunity.org/70849653380.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://8b8c7005-3af0-45a1-8e5b-a6902caa9335.filesusr.com/ugd/dbd7d9_af011ab864b44ce1b75d9e13d6824fb9.pdf?index=trueIn PDF document text
    • http://tuparibuju.atwebpages.com/briton_door_closer.pdfIn PDF document text
    • https://c3438639-6a75-4920-aa4f-d1e0b619354f.filesusr.com/ugd/3be3a7_7d22868c56ec4a6286216dbc1b907d90.pdf?index=trueIn PDF document text
    • https://1de4b56a-3309-4767-83a2-f1bb1ea7c594.filesusr.com/ugd/a6e5e9_1d649cb4e82e48478d37f5b4f12c0ea0.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/001fa695-6f00-4355-87e2-bbaad49118d0/28451376861.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4f6c280e-29b8-417c-9666-923e4746db14/78327266093.pdfIn PDF document text
    • https://37e79482-e567-4eff-b449-6ea9b90d4679.filesusr.com/ugd/cff0cd_2a0bcd76cf3d445bb4e5b975c5aa46c5.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/93a9e3dc-0bfd-414c-bd1d-878f2f6c2c1b/tagalajala.pdfIn PDF document text
    • https://b8f7bc2e-5f90-466c-a76c-b8215bfdb3ae.filesusr.com/ugd/9717d9_d5a6f7a3b6134608a2b6b0319f3228de.pdf?index=trueIn PDF document text
    • https://a7563df4-ba19-4d82-a8a0-b2470d957038.filesusr.com/ugd/61f964_68c826dec06c445785e7b9d76057e4d8.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/0d0e8e9f-244c-4aea-9a49-c4a50a33ed13/why_isnt_my_apple_pencil_pressure_sensitive.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_off000105ad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105AD 5624 bytes
SHA-256: 7d1853bec67bd8f70af423bb39afa4898fa9348bc3576fca11c74f5e23a015bd
font_01_sfnt_off000118bd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x118BD 10568 bytes
SHA-256: a91b35692b0e60d93608a90efde93a0cc478fb02977e5afb7c15b39892b16fc8