Malicious PDF — malware analysis report

Static analysis result for SHA-256 3f9ddf0cf1f8dc0c…

MALICIOUS

PDF

85.7 KB Created: 2021-08-11 05:07:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: b7a763a86705b8d6e7af52939426cbd8 SHA-1: 0cdd3cd9a9c63f0b438fb25a6619a79ad86b47a3 SHA-256: 3f9ddf0cf1f8dc0cceb54293be48df2dc3d2de9ad6e2b69c1e84e64e255d56c7
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external links, many pointing to compromised WordPress sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to redirect users to phishing sites or download further malware. The presence of embedded JS and a link farm suggests an attempt to exploit users through deceptive content or direct malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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://reifenscho.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a44eacdee58---49796710084.pdf
    • https://www.drserapkagan.com/wp-content/plugins/super-forms/uploads/php/files/r5dhnonrq799mmdjc9kcj1pies/tewepamofuwuk.pdf
    • https://jxloanchien.com/style/postimage/file/pakekomazotow.pdf
    • https://interesttour.com/wp-content/plugins/super-forms/uploads/php/files/84b0d93fd0d7f8487f660afe7857b1a5/bezurinipabenokem.pdf
    • http://ahdongjiu.com/upload_fck/file/2021-6-3/20210603125941113997.pdf
    • http://learnersdigest.org/userfiles/file/biwutuvojezavitepavakiv.pdf
    • https://lightupalife.org.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160963f5b27a2d---94687321137.pdf
    • https://djhelaly.com/wp-content/plugins/super-forms/uploads/php/files/21036872d7ed7f65e4a6520e859879b4/wizajuwerekewig.pdf
    • https://lashmakerpro.it/wp-content/plugins/super-forms/uploads/php/files/b552sg3omv1gg5eto5v7ahuvo1/gekusupudaruwolin.pdf
    • https://sieuthimaytinhcu.vn/upload/files/bajuk.pdf
    • http://ride.hu/images/uploads/files/72052332798.pdf
    • https://singaporenotarypublic.com/wp-content/plugins/super-forms/uploads/php/files/40fe7d0d89e7677bd91ec5cb2c280f16/43692576728.pdf
    • http://cedresarquitectura.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a78c793adaa---12913801315.pdf
    • http://www.birapart.com/wp-content/plugins/formcraft/file-upload/server/content/files/160866c0c05a5e---11031135378.pdf
    • https://dodatkireklamowe.pl/web/uploads/files/tuvabovawejifovoroledo.pdf
    • http://cz-synergy.cz/data/file/dutirowo.pdf
    • http://op-gold.com/ck_image//files/56783290670.pdf
    • https://avis-medical.ma/wp-content/plugins/super-forms/uploads/php/files/4b59dad8e8020ec205c9cd48e50d1041/60882919609.pdf
    • http://freetds.net/userfiles/file/82005354025.pdf
    • https://popa.com.br/wp-content/plugins/super-forms/uploads/php/files/250aac9dac1fb3612b1fa81986143e3f/mebesutitubeme.pdf
    • http://doubler-son-capital.com/photos/files/30762387322.pdf
    • http://nfc.soo.jp/file/joviva.pdf
    • https://worldkelo.com/wp-content/plugins/super-forms/uploads/php/files/217375c133b543e61d6fb3efb29504df/rubujokopapakinota.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=count+of+monte+cristo+quiz+answers
    • https://www.assessment.unibe.ch/app/webroot/js/ckfinder/userfiles/files/nazenise.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_off0000e8c4.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE8C4 16792 bytes
font_01_sfnt_off000100d6.bin
ba8cb4b0d769e7c155a36906d65f314b8930ee8c8499cc6b572cf2edff75cafd
pdf-font-stream PDF embedded font (sfnt) at offset 0x100D6 17108 bytes
font_02_sfnt_off00012d0b.bin
d4bd3beba77176d99b907ab704034e70dd3f2faeb414b18cdc03216c86e2745f
pdf-font-stream PDF embedded font (sfnt) at offset 0x12D0B 10876 bytes