Malicious PDF — malware analysis report

Static analysis result for SHA-256 42415d5926f08871…

MALICIOUS

PDF

85.0 KB Created: 2021-09-18 07:30:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 3a231c0b83860e1d9e5d9c2f96551a74 SHA-1: fba1cec9fccd12f10ed1cd7a96823e66f0f5c792 SHA-256: 42415d5926f08871de79d573e4bb490761f00278c02d7c03e454979fe497e2de
156 Risk Score

Malware Insights

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

This PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains a link farm pointing to numerous external PDF files hosted on various domains, suggesting an attempt to distribute malicious content or conduct phishing. The presence of multiple PDF_SEO_DISPOSABLE_LINK_FARM heuristics indicates a pattern of using disposable hosting for these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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://art-gallery.mn/uploads/files/gavimijij.pdf In PDF document text
    • https://turismopontevedra.com/ckfinder/userfiles/files/lorarowatuxadi.pdfIn PDF document text
    • https://sluganarodu.org/userfiles/files/wuxol.pdfIn PDF document text
    • http://kondicionery-vidnoe.ru/upload_picture/file/marepudujefavi.pdfIn PDF document text
    • http://ewhamd.net/upFiles/ckeditor/files/zizarumovafozejoxirozuji.pdfIn PDF document text
    • http://berallebags.com/UploadFiles/FCKeditor/20210906085625.pdfIn PDF document text
    • https://deltaguvenlik.net/userfiles/file/90785109397.pdfIn PDF document text
    • http://novena99.com/uploads/files/202109010015592189.pdfIn PDF document text
    • https://299-45.com/CKEdit/upload/files/12247689778.pdfIn PDF document text
    • http://myhomeinparis.com/userfiles/files/60829796166.pdfIn PDF document text
    • http://www.canadiantreasurer.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612eb1f5aa8c6---71232262276.pdfIn PDF document text
    • http://obras.ru/sites/default/files/uploads/41548642814.pdfIn PDF document text
    • https://brothers-music.com/ckfinder/userfiles/files/kadupidid.pdfIn PDF document text
    • https://groupunsur1.com/contents/files/16248217416.pdfIn PDF document text
    • https://cutletsmeat.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a5ad014b41---12779021463.pdfIn PDF document text
    • http://rebeccaosborne.com/uploads/benikakafowakaturofowuzuv.pdfIn PDF document text
    • https://xn-----6kcabagcgfjsxjciriy6alkh6a7aqk.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/9ce5eefcacb3cfe272c3e47960c39fc6/roxujimapunat.pdfIn PDF document text
    • https://realxenon.ru/uploads/files/panikizitut.pdfIn PDF document text
    • http://gpszone.hu/upload/userfiles/file/xizekukelufebuvoriraba.pdfIn PDF document text
    • https://laurallo.com/ckfinder/userfiles/files/86567532423.pdfIn PDF document text
    • https://www.clubmanizales.com.co/wp-content/plugins/formcraft/file-upload/server/content/files/16131b381253d4---duvaba.pdfIn PDF document text
    • https://arendic.cl/files/nijigekozeliloterireseki.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=grammar+in+use+free+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_off0000e71f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE71F 10536 bytes
SHA-256: 5e62967886d0d5889e08b7e2c7059467d951436e97b11bc7af48d3483ea85269
font_01_sfnt_off0000ff0f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF0F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011721.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11721 18272 bytes
SHA-256: c1221bccd1179a8bafc96a5e8ccd34eca97b4a4b7fc0678400a7584d57103689