Malicious PDF — malware analysis report

Static analysis result for SHA-256 caa1d1ec2062ace1…

MALICIOUS

PDF

78.9 KB Created: 2021-09-07 17:55:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-20
MD5: f12f8d1a1a260fb1153f10a2482209ea SHA-1: 28f1f445924cc24c073ad11217f661da614679c3 SHA-256: caa1d1ec2062ace149028c080c177826045556ba70db19f24cb3ce5f7f0822d4
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links to external websites, many hosted on potentially disposable domains or compromised CMS uploads, suggesting a link farm or phishing lure. The presence of these links and the PDF structure strongly indicate an attempt to redirect users to malicious content, aligning with spearphishing attachment tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

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 http://ahcxdq.com/uploads/file/300056405013.pdf In PDF document text
    • https://betalinktech.com/blmedia/file/ropirapelowakerexonitufax.pdfIn PDF document text
    • https://liniagdanskzydowo.pl/files/45670728032.pdfIn PDF document text
    • http://richmore.kr/uploadfile/fckeditor/file/99967921362.pdfIn PDF document text
    • https://bestcoloringpages.com/userfiles/file/7298428678.pdfIn PDF document text
    • https://szekszardportal.hu/userfiles/file/84607458755.pdfIn PDF document text
    • http://bindashnews.com/userfiles/file/88751946088.pdfIn PDF document text
    • https://tims.ro/ckfinder/userfiles/files/82588889654.pdfIn PDF document text
    • https://maydongy.com/wp-content/plugins/super-forms/uploads/php/files/tfalkb4v62netekgahd7ddsfb7/kerudamixafotomo.pdfIn PDF document text
    • http://www.sunargrup.com.tr/wp-content/plugins/super-forms/uploads/php/files/8el9imtqeuav0rmcgbpmgs0gh7/87312966277.pdfIn PDF document text
    • http://www.vandiestbrandstoffen.be/uploads/files/12982034650.pdfIn PDF document text
    • https://pepinieramontana.ro/ckfinder/userfiles/files/kukanexeliw.pdfIn PDF document text
    • http://bukhatirhomes.com/userfiles/file/84783987609.pdfIn PDF document text
    • http://wbbray.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bc4461608fa---1936418867.pdfIn PDF document text
    • https://omomediacion.com/wp-content/plugins/super-forms/uploads/php/files/0a38cd22d75045629ec15a79412759ae/magawigapapi.pdfIn PDF document text
    • https://www.urban-quartz.co.uk/wp-content/plugins/super-forms/uploads/php/files/cf4b1d97a24b60ce76fc9e40e9d85f62/xivuwedutamumufeletagezov.pdfIn PDF document text
    • https://www.tai.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160a07b6689181---6399052305.pdfIn PDF document text
    • http://slp61.com/clients/e/e2/e296dcecfd7d10ffef0cc83fef253c72/File/sidisopef.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=geologi+sulawesi+pdfPDF 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_off0000cad3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCAD3 19744 bytes
SHA-256: 58addf5b88e0ff543a75c0b18569f4b918f3acb53213eae02334d25d28246977
font_01_sfnt_off0000fe5d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE5D 10596 bytes
SHA-256: d2e6d4d06a522b40ffbab978154a8c72849b2c6605db106a075303dc1c2d7bed
font_02_sfnt_off00011697.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11697 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1