Malicious PDF — malware analysis report

Static analysis result for SHA-256 17ab5f9304d47bea…

MALICIOUS

PDF

81.9 KB Created: 2021-09-07 14:06:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 38745a49b97fce8e8d83615a3f7c92c1 SHA-1: fe1a1c2c04edbcef0e0874e5a3c75345810568e0 SHA-256: 17ab5f9304d47bea32132593281756c9a31e81d3abcca8ec82408988006bb3d7
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with numerous embedded URLs pointing to compromised WordPress sites and other disposable domains. These links likely lead to further malicious content or phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://medvor.ru/uplcv?utm_term=body+image+worksheets+pdf PDF link annotation
    • http://oodow.cn/upload/file/210720164435412095w3g2jglo4ap9.pdfIn PDF document text
    • http://ceskylakros.cz/userfiles/file/dekarulito.pdfIn PDF document text
    • http://baxsporthorses.com/userfiles/file/rafilolodopo.pdfIn PDF document text
    • http://neurooperations.com/ckfinder/userfiles/files/17163513789.pdfIn PDF document text
    • https://diphong.com/uploads/40665017704.pdfIn PDF document text
    • https://himalayanwanderer.com/himalayan/userfiles/files/sivarewadosokilofofavix.pdfIn PDF document text
    • http://www.misshandicap.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160c1cf471fdca---57783367333.pdfIn PDF document text
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160b50a9b73943---jexowobivigumuzinesapa.pdfIn PDF document text
    • https://ristovski.mk/public_html/upload/userfiles/file/21635148634.pdfIn PDF document text
    • https://kes-stv.ru/wp-content/plugins/super-forms/uploads/php/files/cf3d2275fcb314923ac1bea1907ec394/48073671836.pdfIn PDF document text
    • http://fairway.cc/images/blog//file/biragarepe.pdfIn PDF document text
    • http://angeladaniel.de/uploads/files/15869478639.pdfIn PDF document text
    • http://mcutech.net/files/76839437030.pdfIn PDF document text
    • https://cicadit.ro/UserFiles/file/girobeko.pdfIn PDF document text
    • http://www.meglobalinc.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160fb0043ec3e6---botipeg.pdfIn PDF document text
    • http://banlinhkienlaptop.com/userfiles/file/lifilo.pdfIn PDF document text
    • http://teplolux72.ru/upload/file/rupivulaziza.pdfIn PDF document text
    • https://castel.ro/userfiles/file/romofidalunapisop.pdfIn PDF document text
    • https://www.luthier-auxerre.fr/ckfinder/userfiles/files/jaxetikozoxelakopij.pdfIn PDF document text
    • https://adm.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/23fef466855cbb10c1a6040e1c9204a1/81168037564.pdfIn PDF document text
    • https://regalcabs.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1607e1f3a02db2---75799389455.pdfIn PDF document text
    • 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_off0000da73.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA73 17584 bytes
SHA-256: a56c1965d49407ac6d8b82f2e5a14138587baf38143799f6753ff4884b8c60fd
font_01_sfnt_off0001080c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1080C 11140 bytes
SHA-256: 78d5951a459a3ba31f7d6c5a4c9ee2d8dcefbc457d1df3a95b9cea7faa59685d
font_02_sfnt_off00012205.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12205 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1