Malicious PDF — malware analysis report

Static analysis result for SHA-256 8536adcc0b2c5807…

MALICIOUS

PDF

73.9 KB Created: 2021-10-01 02:55:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: cc33b4e75e1ccd65b206589850064f62 SHA-1: ee109f8166cff2361ab50078c58d0bb1adf9dd42 SHA-256: 8536adcc0b2c58077e706cca9f704cbe260d08f156723e5e1d23254dd6de48cb
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple potentially compromised websites. The presence of numerous external URIs and link farm indicators suggests an attempt to distribute malware or conduct phishing operations.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

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://donauwell.at/userfiles/file/pijeraput.pdf
    • http://thenikharvconsultancy.com/userfiles/file/90332958970.pdf
    • http://wedooverseas.com/userfiles/file/22644399615.pdf
    • https://www.agencesramos.com/ckfinder/userfiles/files/magekatow.pdf
    • http://mictrogiang.com/userfiles/files/68928994032.pdf
    • http://hasdeu.md/data/userfiles/files/94901289668.pdf
    • http://toyotarent.kr/FileData/ckfinder/files/20210920_DD8253A87D423BD1.pdf
    • https://greenbins.ca/ckfinder/userfiles/files/riwavasapamolevomeme.pdf
    • https://svenjakretschmer.com/ckfinder/userfiles/files/posadojazirulipamewuj.pdf
    • http://www.rosabrockenhaus.ch/ckfinder/userfiles/files/wirugopemixugususavot.pdf
    • http://101balkon.ru/upload/files/zinuwerijamaboradajidup.pdf
    • https://sakura-bashi.com/uploads/files/202109301734342444.pdf
    • http://arcos-eff.it/userfiles/files/30358634350.pdf
    • http://cbelmira.com/wp-content/plugins/super-forms/uploads/php/files/d5649dcd6cb2bc11610b12f9d6415362/52246737704.pdf
    • http://homeopathyhk.com/files/41545089095.pdf
    • http://le-lemniscus-incandescent.fr/ckeditor/upload/files/77200548881.pdf
    • http://silverk.ru/img/lib/file/59781232941.pdf
    • http://omgmediatank.com/userfiles/files/60045207753.pdf
    • https://marciasmithconsulting.com/wp-content/plugins/super-forms/uploads/php/files/24380a7b2762663155c6024449dc521d/pebobamugavuwenolokis.pdf
    • https://trouver-une-ssii.com/img/pics/files/fedujewezupazil.pdf
    • http://bigbulkbags.ahmadpackages.com/survey/userfiles/files/nujipelanujapizerefurop.pdf
    • http://es-umzuege-transporte.de/wp-content/plugins/super-forms/uploads/php/files/293340319b87d01233dab864674722df/86238429431.pdf
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614b355995c9e---92980571971.pdf
    • http://officinedesign.it/userfiles/files/55744447852.pdf
    • http://royalgoodviewresort.com/Uploads/file/dexawegipatukarusefedenut.pdf
    • http://bantinnhadat.com/users/files/kuduwiwo.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=best+cheap+gaming+phone+in+pakistan
    • 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_off0000b65b.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB65B 16792 bytes
font_01_sfnt_off0000ce6d.bin
7d86282802542a57a36f7565fac9030e24a68febb89441ecdbac67c15224a00c
pdf-font-stream PDF embedded font (sfnt) at offset 0xCE6D 19796 bytes
font_02_sfnt_off000100f5.bin
87ea30bfd2dd5ae15f85c371186dbf7ad9e01b24df26c5e989c41a5a9fc38dd8
pdf-font-stream PDF embedded font (sfnt) at offset 0x100F5 10820 bytes