Malicious PDF — malware analysis report

Static analysis result for SHA-256 83592dd7c7808cb0…

MALICIOUS

PDF

79.7 KB Created: 2021-09-05 23:26:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 923b4f1c8a7588880cc254fe9df3a9d2 SHA-1: 5b10edac34ca7feea4d0ae3a54af629c01863747 SHA-256: 83592dd7c7808cb096964816284f3b4a8aa9a8e0ea1dab9256104a0cc0a3a587
156 Risk Score

Malware Insights

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

This PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links, many pointing to compromised WordPress sites and disposable hosting, suggesting a link farm designed to redirect users to malicious destinations. The document body is heavily obfuscated and unreadable, providing no direct clues about its specific purpose beyond the presence of these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://unnatiwelfareorganization.com/ckfinder/userfiles/files/2121675510.pdf
    • https://lorenzonimmigrationlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c5b822c01e---53649432632.pdf
    • http://kwik-it.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160de0219c29d7---suruma.pdf
    • https://readxyz.org/wp-content/plugins/super-forms/uploads/php/files/a37722f763e336dce5b051678726de12/82578029619.pdf
    • https://terravistahometeam.com/wp-content/plugins/super-forms/uploads/php/files/06462df83e8870bea939589c51b04189/nodapagikuvugeg.pdf
    • http://drinkandshrink.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1608c0d73685d9---lidabef.pdf
    • http://meijialx.com/ckfinder/userfiles/files/nepel.pdf
    • http://artmetinc.com/wp-content/plugins/formcraft/file-upload/server/content/files/160852c1d8d573---netigivixixuvaxiwegok.pdf
    • https://noks.cz/wp-content/plugins/formcraft/file-upload/server/content/files/1606ce65c44246---ruxifunalotuzavibet.pdf
    • http://nakajima-ya.com/upload/save_image/files/jusobaxituvogujezi.pdf
    • http://misterholidaysanprisco.it/userfiles/files/26551981856.pdf
    • http://scan3dsaigon.com/upload/files/najuradesibesori.pdf
    • http://rogo-rotterdam.nl/files/kemozilepoxadasumuneg.pdf
    • https://samowar.me/upload/file/xunajijajopanuferizaleju.pdf
    • http://irvinenott.co.uk/ckfinder/userfiles/files/tufilap.pdf
    • http://xn--80akoseq9f.xn--p1ai/userfiles/file/51146880429.pdf
    • https://www.cdsale.org.au/application/third_party/ckfinder/userfiles/files/13763957104.pdf
    • http://otvorene-srdce.sk/userfiles/file/dadatarofoxiro.pdf
    • https://lightspec.com/wp-content/plugins/super-forms/uploads/php/files/f32c18c783f64880ba8de8c681b181c8/tefodogaw.pdf
    • http://folientastaturen.pl/_data/file/fomuxanebopupe.pdf
    • http://amirafouad.com/uploaded_files/file/36884948600.pdf
    • http://milwaukee.center/userfiles/file/girinatibugunejawowetusa.pdf
    • https://nutstudio.it/userfiles/file/23667025739.pdf
    • https://larustt.com/upload/ckfinder/files/kukuxuradozifobadojunatu.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=conclusions+and+generalizations+worksheets+5th+grade
    • 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_off0000d183.bin
525f39a23c14714978c9b403d3eca445738b2dfc3d7afca6ea35161088b6a29e
pdf-font-stream PDF embedded font (sfnt) at offset 0xD183 17676 bytes
font_01_sfnt_off0000feec.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFEEC 16792 bytes
font_02_sfnt_off00011703.bin
012e9eb40a9deef8088b8f2210c952b246764599955034c55a6d3e8162ed41df
pdf-font-stream PDF embedded font (sfnt) at offset 0x11703 11152 bytes