Malicious PDF — malware analysis report

Static analysis result for SHA-256 aa904252f93281cf…

MALICIOUS

PDF

68.2 KB Created: 2021-09-26 02:59:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 754544898d5823d7e5feab1eb38239de SHA-1: 53b3274ff0455f41e69df2162f4b2ff66d38bef7 SHA-256: aa904252f93281cff7a55e49452dbc9f69cd006a6080b949589d217b125c702e
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, a common technique for executing malicious code within documents. It also exhibits characteristics of a link farm, with numerous URLs pointing to external resources, some of which are hosted on compromised CMS uploads. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9966

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://dongsimkindergarten.com/upload/files/zimubul.pdf In PDF document text
    • http://levne-pohary.cz/UserFiles/File/6371333473.pdfIn PDF document text
    • http://1qjd.com/upload/files/2021-09-25-04-46-39-FIXG1CzQ.pdfIn PDF document text
    • https://rmp-traueranzeigen.de/cms/files/23894896932.pdfIn PDF document text
    • http://www.garriagricola.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140eef285a3a---63183327129.pdfIn PDF document text
    • http://pronobile.com/catalog/file/78904148384.pdfIn PDF document text
    • https://carthink.org/wp-content/plugins/formcraft/file-upload/server/content/files/1614e93741cbfa---32116498800.pdfIn PDF document text
    • https://astoriareiki.com/wp-content/plugins/super-forms/uploads/php/files/4103153d07de0c1131fa1abb7c635107/94177106051.pdfIn PDF document text
    • http://www.sarajevo-inn-grunewald.com/wp-content/plugins/formcraft/file-upload/server/content/files/16142a338eb091---61851833923.pdfIn PDF document text
    • http://iviltra.lt/images/files/38959687617.pdfIn PDF document text
    • http://everbeenmagnet.com/js/upfiles/files/6144876211.pdfIn PDF document text
    • http://marinda.ru/pics/images/file/92332454313.pdfIn PDF document text
    • https://acrgruppe.de/userfiles/file/83644211577.pdfIn PDF document text
    • http://elesi.eu/fichiers/files/80976017360.pdfIn PDF document text
    • http://epicridesnepal.com/files/90178926183.pdfIn PDF document text
    • http://www.sunriseacademy.in/ckfinder/userfiles/files/52894268943.pdfIn PDF document text
    • http://randygordonlawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/difexubarekubegorebom.pdfIn PDF document text
    • https://betalinktech.com/blmedia/file/64435992340.pdfIn PDF document text
    • http://mywayrtk.org/userfiles/file/46578081121.pdfIn PDF document text
    • https://daynexweb.com/upload/ckfinder/files/wagaki.pdfIn PDF document text
    • http://fitviewer.de/files/file/94956910057.pdfIn PDF document text
    • https://hoangphatdanang.com/uploads/image/files/kuvupakiperidadekipesimaj.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=how+many+devices+run+androidPDF 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_off0000ad3a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAD3A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c551.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC551 10744 bytes
SHA-256: 928e0b3fdf61122afc2406a5ba32070c67777b5ae9c547cefad41b1b07e3588b
font_02_sfnt_off0000ddfb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDFB 15000 bytes
SHA-256: 723aee367de63c8e09f359292a508a923333703399f248f0e46497d0d8344e70