Malicious PDF — malware analysis report

Static analysis result for SHA-256 c1dd0a072423a45c…

MALICIOUS

PDF

69.9 KB Created: 2021-09-26 07:00:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 2f0bbc76514969c95b0a3620e5778ed1 SHA-1: f6b3bb6d3f3b90ab68b75a5f1a9393be64c2f219 SHA-256: c1dd0a072423a45c9ccf796363a6cc721175a9c88b887af7700fb5097095489e
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to disposable hosting and appear to be part of a link farm, suggesting a phishing or redirection attempt. While no scripts were explicitly extracted, the PDF structure and heuristic firings indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://samuelben-horin.com/userfiles/file/siwelusevukevikigo.pdf In PDF document text
    • http://studioschicchi.eu/userfiles/files/51763195378.pdfIn PDF document text
    • https://nnkcreations.com/userfiles/file/32179064304.pdfIn PDF document text
    • http://leebyunghun.org/new/upload/board/files/pigedavixuxewen.pdfIn PDF document text
    • http://c-amc.com/upload/files/43505106639.pdfIn PDF document text
    • http://iltorg.ru/upload/file/xerojibum.pdfIn PDF document text
    • https://teamcode.net/upload/files/47662031001.pdfIn PDF document text
    • https://francemonde.news/UserFiles/file/xineratatolulesogar.pdfIn PDF document text
    • http://tmtechvn.com/webroot/img/files/77422135068.pdfIn PDF document text
    • http://epicridesnepal.com/files/lapotisovowaduri.pdfIn PDF document text
    • http://angelofthewinds.net/ckfinder/userfiles/files/notivadapadiwurukawavozo.pdfIn PDF document text
    • http://hertzlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/87959231449.pdfIn PDF document text
    • http://hytechcommunications.com/userfiles/file/26930375753.pdfIn PDF document text
    • http://flooroverstock.com/admin/userfiles/file/wazufujizusozevas.pdfIn PDF document text
    • https://designmaster.in/scgtest/eec-new/codelibrary/ckeditor/ckfinder/userfiles/files/zosukosafu.pdfIn PDF document text
    • http://debandhelder.nl/ckfinder/userfiles/files/nogebipobog.pdfIn PDF document text
    • http://shinhwajudan.com/userData/board/file/3669401880.pdfIn PDF document text
    • http://sakirnoopo.ru/wp-content/plugins/super-forms/uploads/php/files/38e3fb1f19b8f6f17ac5a38f9a190577/53362230238.pdfIn PDF document text
    • http://hotechike.com/files/files/88512578696.pdfIn PDF document text
    • https://srccaa.bdbabymart.com/app/webroot/ckfinder/userfiles/files/54054650604.pdfIn PDF document text
    • http://mirai-kankyo.com/userfiles/files/143028298.pdfIn PDF document text
    • http://griesvoegwerken.nl/UserFiles/file/janurexuvefezotemapo.pdfIn PDF document text
    • http://ckud.handysociality.com/upload/files/15085967185.pdfIn PDF document text
    • http://studiotecnicolari.it/userfiles/files/63658638223.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3CAf4wW3hvY/uplcv?utm_term=grob%27s+basic+electronics+11th+edition+solutions+manual+pdfPDF 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_off0000afc0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAFC0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c7d7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC7D7 11252 bytes
SHA-256: 42973e20f756a5ba70ac50f981e8080bc4a6d06650068b63efb53706b6d01d66
font_02_sfnt_off0000e1e2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1E2 15592 bytes
SHA-256: f425dbd955145a0ac856bd743595c4abccf191a32842fc6789beeadd1d59dba2