Malicious PDF — malware analysis report

Static analysis result for SHA-256 4d0f2db9ff753d10…

MALICIOUS

PDF

74.4 KB Created: 2021-04-23 18:47:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-23
MD5: 5769b2cac250dbd815204cb053fc06ff SHA-1: 15f8c703353457b0d42f5af21064dbcd9721a75a SHA-256: 4d0f2db9ff753d10b71acb2ccf2e9505feeb0426bb84d9a0dbeb182897fb5050
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many pointing to potentially compromised or malicious domains, suggesting a link farm or phishing lure. The document body, though heavily obfuscated, contains metadata related to wkhtmltopdf and a date, but no clear textual lure. No scripts were extracted, but the PDF structure and heuristic firings strongly indicate a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://www.a1touchsolution.nl/sites/default/files/dovav.pdf In PDF document text
    • https://www.osgeurope.com/sites/osg-corporate.dev/files/webform/keborezuvefubivuw.pdfIn PDF document text
    • https://www.natsihwa.org.au/sites/default/files/webform/doxuwekuwazomiloxeri.pdfIn PDF document text
    • https://www.enwidth.com/sites/default/files/webform/resumes/wefegazeketalewawer.pdfIn PDF document text
    • http://pilgrimland.com/sites/default/files/webform/resume-uploads/69774832497.pdfIn PDF document text
    • https://www.viachristi.org/sites/default/files/webform/89070061484.pdfIn PDF document text
    • https://www.uts.cw/sites/default/files/webform/vogoledifekotukedadawen.pdfIn PDF document text
    • https://grossenbacher.co.nz/en/system/files/avoidance-training-certificates/xetomaroronep.pdfIn PDF document text
    • https://www.enwidth.com/sites/default/files/webform/resumes/75468476758.pdfIn PDF document text
    • http://www.sumnercountyhospital.org/sites/default/files/webform/bavowusakixonodokuja.pdfIn PDF document text
    • https://www.osgeurope.com/sites/osg-corporate.dev/files/webform/3563422068.pdfIn PDF document text
    • https://ambrose.edu/sites/default/files/webform/zateguzafafidefezibexe.pdfIn PDF document text
    • https://www.woonsocketri.org/system/temporary/webform/54194604641.pdfIn PDF document text
    • https://www.jts.org.jo/sites/default/files/webform/1653940235.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=best+machine+learning+books+for+absolute+beginnersPDF link annotation
    • https://www.ice.cam.ac.uk/sites/www.ice.cam.ac.uk/files/webform/46273532178.pdfIn PDF document text
    • https://campusrec.princeton.edu/system/files/webform/4552140304.pdfIn PDF document text
    • 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e5b2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE5B2 5548 bytes
SHA-256: b7a23f6238fe4e763543cfebfcd981c47f68c7a93e9ec3879638918a755f61be
font_01_sfnt_off0000f86a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF86A 10700 bytes
SHA-256: 1fea65cebf3afaecb7e08712d228eec9e441c36da0f1fcaef9eab6ecc8935e13