Malicious PDF — malware analysis report

Static analysis result for SHA-256 3da8caab8c2f9744…

MALICIOUS

PDF

75.4 KB Created: 2021-09-16 00:54:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 3fcb063935bda818fc743f09fde8a736 SHA-1: a3ded3224d9dbaa45c85020213e2a8d1ca066e32 SHA-256: 3da8caab8c2f9744f2e2fe942ea9a11c9633b495a9958f76e67a30113a75c56b
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links pointing to compromised WordPress sites and disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and heuristic firings point towards an attack pattern involving redirection to malicious URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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 https://partnermind.cz/images/files/tifosan.pdf In PDF document text
    • https://cplastik.com/data/cms/file/zobokupedefowelixe.pdfIn PDF document text
    • https://stehovani-ostrava.cz/static_pages_files/file/95410217289.pdfIn PDF document text
    • https://www.sgestrecho.es/wp-content/plugins/formcraft/file-upload/server/content/files/1613219eecbcdb---33291634926.pdfIn PDF document text
    • https://westcoastmovers.ca/wp-content/plugins/super-forms/uploads/php/files/j79lumalnrmjrukfupvij31j2f/kudaturegedewuw.pdfIn PDF document text
    • http://star-transform-moscow.ru/uimg/files/vuwumitezo.pdfIn PDF document text
    • https://aldea.work/wp-content/plugins/super-forms/uploads/php/files/ee01590f85fdb0f346718a76137f3633/79888597987.pdfIn PDF document text
    • https://iuoshili.com/upload/users/files/wurax.pdfIn PDF document text
    • https://gs-hemeringen.de/ablage/userfiles/files/56340871013.pdfIn PDF document text
    • https://buyafranchise.org/files/files/pepofaputenixubujiwimi.pdfIn PDF document text
    • http://cungcapbaoduongcuanhatban.com/upload/files/jevitomefevopulawemer.pdfIn PDF document text
    • https://ceramicasvillaflor.cl/UserFiles/File/pugarolerumulevesosa.pdfIn PDF document text
    • http://generaldistco.com/images/file/40352591885.pdfIn PDF document text
    • https://www.sgestrecho.es/wp-content/plugins/formcraft/file-upload/server/content/files/16138dfea9af07---9090765265.pdfIn PDF document text
    • https://fsreloading.com/userfiles/files/vibajutizisafibuloti.pdfIn PDF document text
    • http://abpjseah.news-read.com/upload/files/sunalomodepasitano.pdfIn PDF document text
    • http://xn--80aafkqcanfpgnhbng3b5i9a.xn--p1ai/pict/file/gomopazuridowugaxagaj.pdfIn PDF document text
    • https://glosunspa.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ddb969e16b---vezikida.pdfIn PDF document text
    • https://www.shopveriamici.com/wp-content/plugins/super-forms/uploads/php/files/7pdafruoes01dgk7q01g6fmafb/sazotedu.pdfIn PDF document text
    • http://barexkft.hu/userfiles/file/21581363919.pdfIn PDF document text
    • http://www.sunarnuricomuisvealisverismerkezi.com/wp-content/plugins/super-forms/uploads/php/files/md1bvds66n5sfgtf1v1mhg56e5/36324232989.pdfIn PDF document text
    • http://centromp.it/userfiles/files/81838708577.pdfIn PDF document text
    • http://deltools.com/userfiles/file/25108926334.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=doctor+sleep+subthaiPDF 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_off0000c035.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC035 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d84c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD84C 10608 bytes
SHA-256: 86f1e982a5f5f92f1d9f25be27210d788e672c09462e35cae23700833682a2b7
font_02_sfnt_off0000f06c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF06C 18368 bytes
SHA-256: 0b8c038408028378d8c915f31b8e8427f9265e21db2de6b3ad774219ba3fd0b2