Malicious PDF — malware analysis report

Static analysis result for SHA-256 3e9b2c6ab5981f89…

MALICIOUS

PDF

93.3 KB Created: 2021-06-25 21:22:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4fe1c054f75692d08afa1296f2c2b19e SHA-1: 36028e6474a4459b75950f6a477cd966d3e0fae1 SHA-256: 3e9b2c6ab5981f8940130a0336451998433693f9ef49284532975ed77eea2783
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs that point to compromised CMS upload directories and disposable domains, a common tactic for distributing phishing lures or malware. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or credential harvesting. No scripts were extracted, and the document body was unreadable binary data, suggesting the primary malicious function is the redirection via the link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9918

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 http://grani-tonkogo-mira.ru/wp-content/plugins/super-forms/uploads/php/files/d1ed65ed3227fce69ebc0246a54f01cb/66460839533.pdf
    • https://www.gasserbush.com/wp-content/plugins/super-forms/uploads/php/files/740d62776fa46be7abde51194a2f414f/94873682369.pdf
    • http://asalsold.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b406b9352aa---mitabasi.pdf
    • http://beachfirebrands.com/userfiles/file/3410563934.pdf
    • https://abugfreemind.com/userfiles/file/40800375232.pdf
    • https://nowackleverkusen.de/wp-content/plugins/formcraft/file-upload/server/content/files/160969999cd305---26713003807.pdf
    • https://www.mercedesbenzofaustinservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a9743a98a7e---15074697040.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160984c7e5efb7---namuxekowidewel.pdf
    • https://tasteadmin.com/ckfinder/core/connector/php/custom/wysi_uploads/files/48536872541.pdf
    • http://www.wallisandemmanuel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c8949f5611d---lovumezute.pdf
    • http://jevades.com/aircraft/fckimages/file/58854774633.pdf
    • https://schreinerheusi.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606d9a85b3161---judefebo.pdf
    • https://watfordfairtrade.org/app/webroot/img/files/44480939083.pdf
    • http://hopsch.de/uploads/file/sidawejigixura.pdf
    • http://ahxxzx.com/userfiles/202105/file/keminazodepe.pdf
    • https://swotin.com/wp-content/plugins/formcraft/file-upload/server/content/files/160847b55958e4---tavas.pdf
    • https://cwlighting.com/wp-content/plugins/super-forms/uploads/php/files/6a8aa53d5b27585dc8704676dbf5f8ef/vatatutipu.pdf
    • https://daluxerealty.com/wp-content/plugins/super-forms/uploads/php/files/lne6tfmu6d94tvg62pphnpvje3/lisurusumuwinuw.pdf
    • http://tutek.eu/userfiles/file/45777110360.pdf
    • http://rwdwebwebdesign.com/img-aim/files/xiboruzodawonejin.pdf
    • http://amirafouad.com/uploaded_files/file/44231457473.pdf
    • https://expungemyrecordnj.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a30d249c1d2---67214131269.pdf
    • http://xn--80aamdqpfpr.xn--p1ai/upload_picture/lomamagidatedigasik.pdf
    • http://rethabise.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1607d779e55516---19398829826.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=the+best+ringtone+download+mp3
    • 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f0b8.bin
38ceeef37b69027a27fdd961743dfbab7a2d7b4703b892c074927b8ad0cd5872
pdf-font-stream PDF embedded font (sfnt) at offset 0xF0B8 16920 bytes
font_01_sfnt_off00010927.bin
01a62c37a4c835adbff9c59188f5285bdcba21e22d49da32546965e7ddb3d17d
pdf-font-stream PDF embedded font (sfnt) at offset 0x10927 11200 bytes
font_02_sfnt_off000122d2.bin
0e390f81c295d749ce525b288e3f0f275087279550afc929129b6575f03c7514
pdf-font-stream PDF embedded font (sfnt) at offset 0x122D2 17288 bytes
font_03_sfnt_off00014f77.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x14F77 16792 bytes