Malicious PDF — malware analysis report

Static analysis result for SHA-256 6a7119e838e6f6c2…

MALICIOUS

PDF

82.7 KB Created: 2021-09-12 04:49:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 2bce46189563a1b598c494f5b87f8caa SHA-1: 16da0f71f97c1d0cf9ad32660639e4767f8a952e SHA-256: 6a7119e838e6f6c233bcafc7848c66af871412979bf785bae77b5a6f7bfc205c
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains an embedded JavaScript stream and numerous external URIs, many of which are part of a link farm hosted on disposable or compromised domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware delivery through these links. The embedded JavaScript may be used to further obfuscate the redirection or exploit vulnerabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://philabc.ru/uplcv?utm_term=zombie+survival+android
    • http://themetamorphoseprogram.com/userfiles/file/55326066271.pdf
    • http://safedoorsystems.com/cmsimages/file/63432617856.pdf
    • http://autoklej.pl/app/webroot/media/files/gubupaxa.pdf
    • http://dtjxbpzx.com/filespath/files/20210912031247.pdf
    • http://elenasteele.com/wp-content/plugins/formcraft/file-upload/server/content/files/161351c8faebff---68350182851.pdf
    • http://recruiters-zone.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138175b377f6---99314996487.pdf
    • http://dierenwinkelindex.nl/images/uploads/mujibetubaduw.pdf
    • http://slhospital.com/upload/fckeditor/file/93670947695.pdf
    • http://optimumnieruchomosci.pl/uploads/userfiles/files/82627923276.pdf
    • https://bestcoloringpages.com/userfiles/file/90906319132.pdf
    • https://defrokatilai.lt/images/files/duzesarimanenavikibegi.pdf
    • http://topbuild.net/content/xuploadimages/file/vowiduzexatozowepexitu.pdf
    • http://asiancfea.org/userfiles/file/88628257020.pdf
    • https://htchninc.com/d/files/57592619154.pdf
    • http://khodahoanglang.com/admin/webroot/upload/image/files/fedobozagalari.pdf
    • http://businessdevelopmentcenter.pl/uploads/userfiles/files/voralajavutenuperodozobo.pdf
    • https://www.studioline.ie/ckfinder/userfiles/files/xufuletenulise.pdf
    • https://maydangson.com/vietkiendo/upload/file/vesovopajokirekon.pdf
    • http://ormansagszive.hu/upload/file/49973038837.pdf
    • https://bibonatura.hu/ckfinder/userfiles/files/67690257420.pdf
    • http://bagpack.com.np/wp-content/plugins/formcraft/file-upload/server/content/files/16130dedb7bbf4---84712833046.pdf
    • http://officegate.biz/admin/fck_upload/file/99758225575.pdf
    • https://donnasalon.ru/wp-content/plugins/super-forms/uploads/php/files/b402ad6cec70ad34f12386eb952cf3ce/55982454756.pdf
    • http://www2.grupoksl.com.br/js/ckfinder/userfiles/files/miwirerezijawidafegorikem.pdf
    • 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_off0000dfbe.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xDFBE 16792 bytes
font_01_sfnt_off0000f7d5.bin
168156a480d58dd29cfa12a2dca74852440e09e3ea596160ab6a5100ccf506c5
pdf-font-stream PDF embedded font (sfnt) at offset 0xF7D5 10580 bytes
font_02_sfnt_off00010fe7.bin
b22a40ede3870e32dacdcbdacba047b20a3fcf45e16e27554900e9a58b4a10e3
pdf-font-stream PDF embedded font (sfnt) at offset 0x10FE7 17328 bytes