Malicious PDF — malware analysis report

Static analysis result for SHA-256 8b776c6f85eed11a…

MALICIOUS

PDF

68.0 KB Created: 2021-10-03 09:00:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 1b52e6c245791d901b39f73b00c9ca8a SHA-1: 9ed3d484f62e76cf7b60c1add20b4d79811f933b SHA-256: 8b776c6f85eed11aab3526edc9e8025be4d691fc89f758d7be8ac11bd248a13b
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and a machine learning classifier indicated a high probability of maliciousness. The document contains an embedded JavaScript stream and numerous external URIs, many of which point to disposable hosting or compromised CMS uploads, suggesting a link farm designed to redirect users to malicious content. The presence of JavaScript indicates an attempt to execute code within the PDF viewer.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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 http://lifeisartfoundation.org/sites/default/files/images/userfiles/file/9100086165.pdf In PDF document text
    • https://sopkambing.com/contents/files/savovaxajarepumi.pdfIn PDF document text
    • http://handsonmontessoripk.com/userfiles/files/dusolipevuxutisagara.pdfIn PDF document text
    • http://szsahsh.com/uploads/files/xugemin.pdfIn PDF document text
    • http://smepil.com/ckeditor/userfiles/files/kutomoxurefejufabefabab.pdfIn PDF document text
    • http://aluminial.pnh.pt/js/ckfinder/userfiles/files/69120676583.pdfIn PDF document text
    • http://romengo.com/ckfinder/userfiles/files/38541893441.pdfIn PDF document text
    • https://bokseinstituttet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/1614e224ae2b71---46025590309.pdfIn PDF document text
    • http://sambometal.com/dataroom/file/gajesivavameselotiboneteg.pdfIn PDF document text
    • https://aymsoft.us/aym_image/files/35763065149.pdfIn PDF document text
    • http://belniig.by/public/file/36010086732.pdfIn PDF document text
    • http://itemclinicchina.com/ckupload/files/divobip.pdfIn PDF document text
    • http://eduomania.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f0ca5a5b72---45623524146.pdfIn PDF document text
    • http://eko-inwest.eu/upload/file/nefadekiwalolap.pdfIn PDF document text
    • http://studiosiriosrl.it/userfiles/files/gixamilotewatofawe.pdfIn PDF document text
    • http://labemweller.medianet-shop.de/userfiles/editor_files/file/70301683152.pdfIn PDF document text
    • https://triyoga-tv.ru/userfiles/file/3431205329.pdfIn PDF document text
    • http://unleadedcoffee.cz/soubory/18468075502.pdfIn PDF document text
    • https://www.reliancecareuk.com/wp-content/plugins/super-forms/uploads/php/files/10406c5f848a9f4f22348aa2c32aa0c9/zevupevakexulep.pdfIn PDF document text
    • http://golfproradost.cz/webpagebuilder/ckfinder/userfiles/files/37449998038.pdfIn PDF document text
    • http://ffarchitettura.it/userfiles/files/77327324073.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=what+do+you+like+to+write+aboutPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000add3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xADD3 14628 bytes
SHA-256: 137882c11138984fdc8fb723ddb12962d3ec136cabec840920a625a6373b08d8
font_01_sfnt_off0000d27c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD27C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000ea93.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA93 10596 bytes
SHA-256: 1d47ae7c0914801323441d24fde195b92fb17e7f2b419c9c955966fe0b28f797