Malicious PDF — malware analysis report

Static analysis result for SHA-256 48838d1b00660377…

MALICIOUS

PDF

80.4 KB Created: 2021-10-17 08:14:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: aeecd587f22b2c4d963ecff0b7b128c6 SHA-1: bc7b404e17564a42a8f7bf2d47bec00da662160c SHA-256: 48838d1b00660377b3a15d05783aacca631cefdcc2d026241dfb2df1030514f8
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised websites or disposable domains, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' confirms the nature of the links, and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' highlights the use of compromised infrastructure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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://nomylo.ru/uplcv?utm_term=examples+of+miscellaneous+items PDF link annotation
    • http://ecocj.com/userfiles/file/20211005070911.pdfIn PDF document text
    • https://extremedriveline.com/ckfinder/userfiles/files/kusibugatufuragedup.pdfIn PDF document text
    • https://saglamahsapkutu.com/img/editor/image/file/22727599844.pdfIn PDF document text
    • http://reklamavysocina.cz/UserFiles/File/1488834777.pdfIn PDF document text
    • http://matsusushionline.com/uploads/files/90874953465.pdfIn PDF document text
    • http://gemculture.com/userfiles/file/gidemegixe.pdfIn PDF document text
    • http://www.birapart.com/wp-content/plugins/formcraft/file-upload/server/content/files/16149e397255b5---mafowetiwoton.pdfIn PDF document text
    • http://embeddedhr.com/ckfinder/userfiles/files/punenaguwodavumi.pdfIn PDF document text
    • http://atomleasing.ru/media/File/wesuga.pdfIn PDF document text
    • http://magicfood-cn.com/files/20210923120847.pdfIn PDF document text
    • https://kimcert.com/E/file/vawegukuruvegoxa.pdfIn PDF document text
    • http://760_709737661.mildmedia-dev.eu/uploads/userfiles/files/fodedepadalivuwemawuxome.pdfIn PDF document text
    • http://opsir.eu/files/file/fojosasanirekilutedadiw.pdfIn PDF document text
    • http://industrialsupplies.pk/userfiles/files/rerazepapetelal.pdfIn PDF document text
    • https://isosklo.cz/uploads/tiwobuwuzijomajubo.pdfIn PDF document text
    • https://vnsteeldetailing.com/UserFiles/files/wegali.pdfIn PDF document text
    • http://abwhopewell.com/uploads/files/5289066821.pdfIn PDF document text
    • http://hunicorn.hu/userfiles/file/barebutoranopa.pdfIn PDF document text
    • https://www.chortho.co.uk/wp-content/plugins/super-forms/uploads/php/files/8bt8618pic32evdrukpkj9rqg9/89979754798.pdfIn PDF document text
    • http://www.advancedevents.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16145041c47599---tiwifomugefub.pdfIn PDF document text
    • http://batiment-tunisie.com/userfiles/file/jobonixivodudutuf.pdfIn PDF document text
    • http://zaiger.ru/img/file/45369060262.pdfIn PDF document text
    • http://decom.pro/admin/ckfinder/userfiles/files/49738609024.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_off0000d3a9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD3A9 10724 bytes
SHA-256: 7a683a8ec5cf99d2dbc5c5e68c6ac11f7ed4a9750104eb610a776998cdaa32a3
font_01_sfnt_off0000ec51.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC51 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010463.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10463 18044 bytes
SHA-256: 11bee311093ca13dd566b7174e139f7b9e3510b09ca35abe6dd254994d63bf93