Malicious PDF — malware analysis report

Static analysis result for SHA-256 5de2a425c7c2d893…

MALICIOUS

PDF

75.6 KB Created: 2021-09-08 15:48:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: f66f8784f918cbe88853de7e13c54014 SHA-1: a2852c41fda162ae62470c4015f6c263fa5dd5a2 SHA-256: 5de2a425c7c2d8938372b53e818a964bdec6f785afd1bcab8d2536e1aff011f0
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains a link farm pointing to multiple domains, many of which appear to be compromised WordPress sites hosting PDF files. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or malware delivery. The embedded URLs suggest an attempt to lure users to external sites, potentially for credential harvesting or further exploitation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://mertlakustika.cz/images/pages/file/4989061935.pdf In PDF document text
    • https://ekransamara.ru/files/xubosejepa.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1612f5380491c8---48580113285.pdfIn PDF document text
    • https://seroinstitute.com/wp-content/plugins/super-forms/uploads/php/files/dcbdc4652aa889889321d4824e0f262d/83000537518.pdfIn PDF document text
    • http://atrsara.ir/resource/files/75208950402.pdfIn PDF document text
    • https://dmddsgn.com/wp-content/plugins/super-forms/uploads/php/files/b47c33b92da1726027c617f02ab0628c/rajexuwanaseb.pdfIn PDF document text
    • https://bbensonmft.com/wp-content/plugins/super-forms/uploads/php/files/0724f25610d269dba448bf860e118232/35034272127.pdfIn PDF document text
    • https://brawlcall.com/ckfinder/userfiles/files/gaduzerelawipogone.pdfIn PDF document text
    • https://stewsites.com/wp-content/plugins/super-forms/uploads/php/files/5f5555199b6e6855821d26b6137842f7/nidez.pdfIn PDF document text
    • https://givemeit.ru/wp-content/plugins/super-forms/uploads/php/files/8fedcb200a02f46bd8cb6f8954a4e4f9/91582773659.pdfIn PDF document text
    • https://globalcircle.club/userfiles/file/4097026873.pdfIn PDF document text
    • https://118highschool.am/wp-content/plugins/super-forms/uploads/php/files/c9d75d1a0ed55b2987f3beff45e355c5/65266344535.pdfIn PDF document text
    • http://praxis-greve-polley.de/web/editor/files/tolasezusevimoxen.pdfIn PDF document text
    • http://wingmanplanningdemo.com/userfiles/files/1302672923.pdfIn PDF document text
    • http://mgtuae.com/uploads/file/gejasefakujujepopiwazasa.pdfIn PDF document text
    • http://icbiz.ru/userfiles/file/23749914280.pdfIn PDF document text
    • https://groupekineconcept.com/userfiles/file/61565533558.pdfIn PDF document text
    • https://capital-publishing.com/ckfinder/userfiles/files/53065326472.pdfIn PDF document text
    • http://taiwangallant.com/uploads/files/202109080632161844.pdfIn PDF document text
    • https://xistenze.nagydavid.com/files/files/16624588266.pdfIn PDF document text
    • http://xn--80ackbssfuieecff0e8c.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/j91dal00gul44utepq365o3vd1/pikasevotit.pdfIn PDF document text
    • http://cabini.it/userfiles/files/8783728913.pdfIn PDF document text
    • http://chetaomaynganhnhua.com/uploads/files/sobol.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=ghatna+chakra+geography+2018+pdf+in+englishPDF 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_off0000bb89.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBB89 19260 bytes
SHA-256: 78dbd2546b99ba9218be05081d31d42651486da623f9eda77cbeb9432c33e9d0
font_01_sfnt_off0000ed90.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED90 11648 bytes
SHA-256: 26ef5b15c46684af1ba950e7d27e696d1f0db3f5a60a40b29335746eee942709
font_02_sfnt_off00010930.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10930 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1