Malicious PDF — malware analysis report

Static analysis result for SHA-256 534a7775e65a5b2e…

MALICIOUS

PDF

88.8 KB Created: 2021-06-28 07:19:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 68ab72c340cd39de958e9d3777869477 SHA-1: 658f6f10f52fa97baa95fff18186f5d36a69f31b SHA-256: 534a7775e65a5b2e4d30e3797b3847e10ab30985ddf7a459c98f1767f6aeefd8
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains a link farm pointing to numerous distinct hosts, many of which appear to be compromised WordPress installations hosting PDF files. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the nature of the link farm and the embedded URLs suggest an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://www.lumisolar.pe/wp-content/plugins/formcraft/file-upload/server/content/files/1609acec587197---84263870025.pdf In PDF document text
    • https://bbmint.com/userfiles/file/buzofere.pdfIn PDF document text
    • https://www.coconutlodge.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609f15465bc5f---79258061713.pdfIn PDF document text
    • http://www.infranetltd.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a796f5cf59a---dujunidasulopavixibuvosug.pdfIn PDF document text
    • http://trungnguyenjsc.vn/uploads/image/files/kulupus.pdfIn PDF document text
    • https://www.eziblank.com/wp-content/plugins/super-forms/uploads/php/files/mcgg4p257q6o5ma2r0i149s892/69421012576.pdfIn PDF document text
    • http://www.alwaysflorida.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e201e5dd52---76440448721.pdfIn PDF document text
    • http://softwarefactory.nl/images/file/ravevurupaporuru.pdfIn PDF document text
    • https://aulacvn.com/upload/fck/file/27564159891.pdfIn PDF document text
    • http://www.kreasoft.mx/wp-content/plugins/formcraft/file-upload/server/content/files/160a77bbad1c86---berenafavexadezuzigoluv.pdfIn PDF document text
    • https://advancedbusiness.co/wp-content/plugins/super-forms/uploads/php/files/39cb077f0d0aececd0a188bae09b0c59/17710003365.pdfIn PDF document text
    • http://www.majoriscambio.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160c4e4c79fdd0---timitewanugubarukufudami.pdfIn PDF document text
    • https://www.sgestrecho.es/wp-content/plugins/formcraft/file-upload/server/content/files/160a1b968dfd68---4654664504.pdfIn PDF document text
    • https://alatheir.com/atheirwsfiles/file/megup.pdfIn PDF document text
    • https://marksiegeldds.com/wp-content/plugins/super-forms/uploads/php/files/884ef861cdd1279f16da27d9093b6b37/64746211140.pdfIn PDF document text
    • https://markzone.az/wp-content/plugins/super-forms/uploads/php/files/lbla3fu0tdc63ftrvev7cq39sg/vuvemubazivulur.pdfIn PDF document text
    • https://aquafilling.com/userfiles/file/gojevun.pdfIn PDF document text
    • http://poltinik.ru/userfiles/file/28996360559.pdfIn PDF document text
    • https://baxsporthorses.com/userfiles/file/67946170578.pdfIn PDF document text
    • http://aeskulap24h.de/wp-content/plugins/formcraft/file-upload/server/content/files/160afa7e757bb7---puninodatif.pdfIn PDF document text
    • https://msr-hudsonproperties.com/wp-content/plugins/super-forms/uploads/php/files/313d5f6966f2093c445271bbd3cf7ccc/13763963062.pdfIn PDF document text
    • https://thejinglelab.com/wp-content/plugins/super-forms/uploads/php/files/84aodmeuk51uhppho56e5h0aba/87756852801.pdfIn PDF document text
    • https://weblative.com/wp-content/plugins/super-forms/uploads/php/files/b46nq6mtmfst0kjoi3f1vn2f05/26442214378.pdfIn PDF document text
    • https://rebates.forex/wp-content/plugins/super-forms/uploads/php/files/734o5vp01a9fbcsqtk08tull72/bisazovunebiganuri.pdfIn PDF document text
    • https://canadianrelocation.net/wp-content/plugins/formcraft/file-upload/server/content/files/16077a3408f1aa---doduvegosivaza.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=how+to+set+up+a+system+of+equationsPDF link annotation
    • 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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f602.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF602 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010e14.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E14 18080 bytes
SHA-256: 4ba7961eab0b8461a1d4d9eb358acd3b204debab9f72a3f8fdb8cbb5756e0bb9
font_02_sfnt_off00013cda.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13CDA 10808 bytes
SHA-256: 9db87e61911b50dc14ff8aa20327f6711f3a43c6aab1d0179af44eb244e45d75