Malicious PDF — malware analysis report

Static analysis result for SHA-256 d4bf86497b6e0850…

MALICIOUS

PDF

72.9 KB Created: 2021-04-13 14:36:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-29
MD5: 5edc6e17be746b27895daed35ce7da6c SHA-1: daaec373d08190ff163b277c6e80461ea9405732 SHA-256: d4bf86497b6e0850f5e917b396bd11f4287d15b7d3eaa034ea40b956f4d79295
126 Risk Score

Malware Insights

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

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous embedded URLs, many pointing to potentially compromised or malicious sites, suggesting a link farm or phishing lure. The PDF structure and embedded content, while obfuscated, are consistent with attempts to redirect users to malicious destinations.

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.mainephilanthropy.org/sites/default/files/wimatetomowitiki.pdf In PDF document text
    • https://ambrose.edu/sites/default/files/webform/fenalop.pdfIn PDF document text
    • https://www.osgeurope.com/sites/osg-corporate.dev/files/webform/10654010608.pdfIn PDF document text
    • https://www.woonsocketri.org/system/temporary/webform/konoju.pdfIn PDF document text
    • https://www.natsihwa.org.au/sites/default/files/webform/19026354442.pdfIn PDF document text
    • https://www.osgeurope.com/sites/osg-corporate.dev/files/webform/nutuzisujobipusife.pdfIn PDF document text
    • https://grossenbacher.co.nz/en/system/files/avoidance-training-certificates/tatemomolefifepa.pdfIn PDF document text
    • http://klm3fg.grhosting.cz/sites/default/files/webform/files/tekuxegejarikuferibo.pdfIn PDF document text
    • https://www.ofalloncasting.com/sites/default/files/webform/81254010544.pdfIn PDF document text
    • https://www.osgeurope.com/sites/osg-corporate.dev/files/webform/keborezuvefubivuw.pdfIn PDF document text
    • https://www.visitsavannah.com/sites/default/files/webform/fukixuliwidopisoduzurapi.pdfIn PDF document text
    • http://www.pbttphtk.gov.my/sites/default/files/webform/1232685222.pdfIn PDF document text
    • http://www.friendlycc.com/sites/default/files/webform/16921441106.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=saga+of+blue+eyes+white+dragonPDF link annotation
    • https://gradfutures.princeton.edu/system/files/webform/pelafo.pdfIn PDF document text
    • https://printandmail.princeton.edu/system/files/webform/85064040694.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d0e6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD0E6 5488 bytes
SHA-256: e4cb7dbc2c8c05ca8807e9c6cdec5fe35ba90c365fd8d501929af9feb19201c8
font_01_sfnt_off0000e390.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE390 10856 bytes
SHA-256: 71e11e8bb0bb147de561d2fbbc34952d7d7a5a6f1b64d71fd13103d082be380e
font_02_sfnt_off000108ae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108AE 4324 bytes
SHA-256: cd94ef65598b1866d0653cdd88243d989fd81359c0e770c2d3a4858f1c2f6d34