Malicious PDF — malware analysis report

Static analysis result for SHA-256 4f844f508f2eaa06…

MALICIOUS

PDF

74.4 KB Created: 2021-06-21 10:11:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-11
MD5: 1d154580a37458c7686bec57a81caaf4 SHA-1: 78e6f99f547ca8c8c106432330d657386c753d78 SHA-256: 4f844f508f2eaa0660f301117b9d04ea0b2ff4bbf78d837e94bb7d730b075218
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to multiple compromised WordPress upload directories, suggesting an attempt to distribute malicious files. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9999

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://airshow-bg.com/file/66684318744.pdf In PDF document text
    • http://aeskulap24h.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b753e80959---47810186371.pdfIn PDF document text
    • http://www.alquilerbares.com.ar/wp-content/plugins/formcraft/file-upload/server/content/files/1607bd5ca2b8aa---77509902968.pdfIn PDF document text
    • https://faprosid.com/file/biduxexijoneg.pdfIn PDF document text
    • https://altinhediyeler.com/calisma2/files/uploads/41895603047.pdfIn PDF document text
    • http://ride.hu/images/uploads/files/58108205529.pdfIn PDF document text
    • https://www.hausbootgeiseltalsee.de/wp-content/plugins/super-forms/uploads/php/files/etrdvq20kqq2s6vfhfuf82abag/wawere.pdfIn PDF document text
    • http://dlt-nkp.com/fileupload//file/fugefelawo.pdfIn PDF document text
    • http://aksaaydinlatma.com/img/editor/image/file/26811498246.pdfIn PDF document text
    • http://nedirajtebosnu.net/userfiles/file/72391663779.pdfIn PDF document text
    • https://simovi.mx/wp-content/plugins/formcraft/file-upload/server/content/files/1607bee045a8e9---nibajomasunuxidujajej.pdfIn PDF document text
    • https://securityguardsupply.org/php/uploads/file/23941906664.pdfIn PDF document text
    • https://genericdiabeticteststrips.com/userfiles/files/40982859821.pdfIn PDF document text
    • https://amd-export.com/site/upload/file/xakadudegujewuwenawinif.pdfIn PDF document text
    • https://atlanthealth.com/wp-content/plugins/super-forms/uploads/php/files/4a23e7660a7bc7006a7c75f31b3e6ba7/30049611524.pdfIn PDF document text
    • https://fieldofgreen.com/wp-content/plugins/super-forms/uploads/php/files/b7891935096da7adbe91277c802b71b1/56545969672.pdfIn PDF document text
    • http://venusland.vn/app/webroot/img/files/nibofovim.pdfIn PDF document text
    • http://asesorialuishervas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b38e7a15497---tiwataminosetatijas.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=supersu+flashable+zipPDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e533.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE533 5280 bytes
SHA-256: 06c99ca5324cfa5f9d5e37a997096f0ec850be4d89cfc93c3dadb0e808439024
font_01_sfnt_off0000f723.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF723 11104 bytes
SHA-256: 4f130fe22840b9e47ea7a115716554aff35693494f9bd1f89136a28d60613a02