Malicious PDF — malware analysis report

Static analysis result for SHA-256 e31dd27f0fa040ea…

MALICIOUS

PDF

76.5 KB Created: 2021-09-20 12:49:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 94ee49ab4e58391a37f4a8a890f8e9e3 SHA-1: 7be40611e3517fcfb2de4083014f872e03768bcd SHA-256: e31dd27f0fa040ead21ff97445690704b783cbad9c8d021b2d4357190586ca39
156 Risk Score

Malware Insights

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

This PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with numerous URLs pointing to disposable hosting and compromised CMS upload directories. These links are likely designed to redirect users to malicious or phishing content, aligning with the characteristics of a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9908

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://aydinservis.com/ckfinder/userfiles/files/71181242226.pdf
    • http://diagnosticaedilizia.com/userfiles/files/guvejaxo.pdf
    • https://dsodrecital.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131ae062703b---kasefu.pdf
    • http://accessiblevehicleservices.com/userfiles/file/81039421047.pdf
    • http://objetivovender.com/wp-content/plugins/formcraft/file-upload/server/content/files/16142a68688129---tuvepuwepilovojedaxukikor.pdf
    • http://kingsfci.com/userfiles/file/sevewososuwotatejenitak.pdf
    • http://vegasoft.hr/wp-content/plugins/formcraft/file-upload/server/content/files/16142822f6cbe6---wadowemoju.pdf
    • https://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/rrilq577jpk7dtfg3uhrqgkmf3/86322352694.pdf
    • http://qdjshg.com/files/file/75138143523.pdf
    • https://tourpon.kr/FileData/ckfinder/files/20210906_C55F9AF9E57EDB00.pdf
    • http://monteconsultants.com/image/upload/File/19525880934.pdf
    • http://dymenahealthcare.com/upload/fckeditor/file/81172703304.pdf
    • http://changrung.com/ckfinder/userfiles/files/3310133826.pdf
    • http://squarcialupirelaxinchianti.com/writable/public/userfiles/file/96238572697.pdf
    • http://mictrogiang.com/userfiles/files/puvolokaxi.pdf
    • http://artecgroupservices.com/imagenes/file/woromunoworopibasomof.pdf
    • https://thediamangroup.com/_images/files/jutixerilevinadexuvuzek.pdf
    • https://hoangphatdanang.com/uploads/image/files/xunawimuma.pdf
    • http://prttour.ca/FileData/ckfinder/files/20210905_3096BF8B5D3583C6.pdf
    • http://millionsdiscount.com/mo_images/files/jotekim.pdf
    • https://firesystem.ro/imagini_ws/89060089327.pdf
    • http://mgtofubbq.com/uploads/files/59946331916.pdf
    • https://wsbtitan.com/images/file/36078123590.pdf
    • http://egitara.com/upfiles/files/diwonok.pdf
    • http://limpiasol.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141c402668a2---20457020978.pdf
    • https://samsungklimalar.com/upload/ckfinder/files/97513092807.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=square+root+of+3x
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c830.bin
6323a44042a363dd49b76854ae5cda5d4f6b7c289b775cf142fa6cefe21e857d
pdf-font-stream PDF embedded font (sfnt) at offset 0xC830 17128 bytes
font_01_sfnt_off0000f489.bin
4d7bb9438e52cc8646b1dabba7cb01806ded81cd3f5fc9019d2761cb14111000
pdf-font-stream PDF embedded font (sfnt) at offset 0xF489 10392 bytes
font_02_sfnt_off00010c49.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10C49 16792 bytes