Malicious PDF — malware analysis report

Static analysis result for SHA-256 a5d7998ecc25c5f9…

MALICIOUS

PDF

86.6 KB Created: 2021-06-28 09:19:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e0f3949cb0493919d2198f77f23c93bc SHA-1: 19b27c27e24c51228b9b089d3138b59efe1ca77f SHA-256: a5d7998ecc25c5f9f28dd4c90457e0ead46248ded18a842d2dc663d520c34234
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains a link farm with numerous URLs pointing to compromised CMS upload directories, as indicated by the 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' heuristics. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the structure and URL patterns are consistent with malicious PDFs designed to lure users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

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://www.lesson-online.org/wp-content/plugins/super-forms/uploads/php/files/kuo11vmr9msrmvc05184n0f3n5/tekujunemejubuwokad.pdf
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/16094726c8157f---wugefiv.pdf
    • https://kuechentreff-schmid.de/wp-content/plugins/super-forms/uploads/php/files/2410930qkkp8rokatgtvdolj8f/fulavelujajarizetubedek.pdf
    • https://directprocessors.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608c318ed680f---xafebodiz.pdf
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/0231547980b32002123b14074907c7b4/muziw.pdf
    • http://ankaser.com/userfiles/file/putun.pdf
    • http://oneself.pro/wp-content/plugins/formcraft/file-upload/server/content/files/1606cd3fb5bba5---nisinego.pdf
    • https://longhoang.vn/upload/files/45509061023.pdf
    • http://www.realisthotel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609927e6db0ae---pabigemokinu.pdf
    • http://www.lavalledesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d1a71037e1---sudatefunelixelazimok.pdf
    • http://alphabodysupplements.com/newerac2c/userfiles/file/74307289672.pdf
    • https://www.pferde-fuer-unsere-kinder.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606d2536c8806---79820643980.pdf
    • https://islandsvefir.is/wp-content/plugins/super-forms/uploads/php/files/gparo2f0k8jevm04ef8kv49875/55171624502.pdf
    • https://ateneoarbonaida.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b1da05d6457---nakupinikorolagim.pdf
    • https://dazzlin.co.uk/wp-content/plugins/super-forms/uploads/php/files/129b743ab231a89a2315db273b45b8d5/91603261636.pdf
    • https://www.saltriot.com/wp-content/plugins/super-forms/uploads/php/files/3db4d4c835bf2e9973fc97ba87f1cdd5/virerorinegigaz.pdf
    • https://kvkumariajnkvv.org/singhania/downloads/file/masirafojivefibenod.pdf
    • http://sunarfactory.com/userfiles/files/xizakotajerupewunap.pdf
    • http://panhongbo.com/ckfinder/userfiles/site_eachfun_com/files/samanodex.pdf
    • https://wecafephuket.com/wp-content/plugins/super-forms/uploads/php/files/3k45bnl40h0esgg3v4gi4p8toh/nikagumonaxapuzobakaraxez.pdf
    • https://misionesmedellin2030.com/wp-content/plugins/super-forms/uploads/php/files/kkc97h3eoc2t4csi1qg9pjnv43/jegosizu.pdf
    • https://alatheir.com/atheirwsfiles/file/55821970925.pdf
    • https://micsys.in/userfiles/file/1593107712.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=the+house+of+silk+anthony+horowitz+pdf+download
    • 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_off0000ecf9.bin
810b27d3fd3a7e08e4ae9d9896a0bfcae267edff9a1a6c39ade49e4077baa896
pdf-font-stream PDF embedded font (sfnt) at offset 0xECF9 17476 bytes
font_01_sfnt_off00011b18.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11B18 16792 bytes
font_02_sfnt_off0001332f.bin
f952419b565fb07d51b944aa6d036a814634f29e4eec0a877b557944daf65c54
pdf-font-stream PDF embedded font (sfnt) at offset 0x1332F 11008 bytes