Malicious PDF — malware analysis report

Static analysis result for SHA-256 d1ecba9046c0e8ca…

MALICIOUS

PDF

75.4 KB Created: 2021-04-18 00:36:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-21
MD5: 0d5aa300642f68c7865a874d0af39cdb SHA-1: be86185032eb9f9e74567797a462b79ac361747b SHA-256: d1ecba9046c0e8cadae7ad1f5fe7fd9f4771c79ee498f391de243d71b00f5829
126 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics, including a high-confidence ML classifier and ClamAV, indicating malicious intent. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic suggests it functions as a link farm, directing users to potentially malicious or phishing sites. While no scripts were explicitly extracted, the presence of embedded URLs and the nature of the link farm heuristic point towards an attempt to redirect users to external resources for further compromise.

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 http://klm3fg.grhosting.cz/sites/default/files/webform/files/22206840813.pdf In PDF document text
    • http://oaklandchildcare.org/sites/default/files/webform/26688185713.pdfIn PDF document text
    • http://oaklandchildcare.org/sites/default/files/webform/85278691340.pdfIn PDF document text
    • https://www.osgeurope.com/sites/osg-corporate.dev/files/webform/35757612566.pdfIn PDF document text
    • https://www.jwico.com/sites/default/files/webform/49109440539.pdfIn PDF document text
    • https://www.jwico.com/sites/default/files/webform/vuvosiritixulufanili.pdfIn PDF document text
    • http://www.pbttphtk.gov.my/sites/default/files/webform/3018222411.pdfIn PDF document text
    • http://klm3fg.grhosting.cz/sites/default/files/webform/files/56601188302.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=how+to+train+legs+for+strengthPDF link annotation
    • https://lib.asu.edu/system/files/webform/85824103047.pdfIn PDF document text
    • https://drones.princeton.edu/system/files/webform/voretazejujuwewoz.pdfIn PDF document text
    • https://umatter.princeton.edu/system/files/webform/requests/tutoturabawukaxubudevodor.pdfIn PDF document text
    • https://ubmemeaensoprod.s3.amazonaws.com/ifsec_international/call_for_papers/2021/03/33404153997.pdfIn PDF document text
    • https://minorsoncampus.princeton.edu/system/files/webform/27732669772.pdfIn PDF document text
    • https://lib.asu.edu/system/files/webform/bejugejotofetuxiw.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_off0000dee3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDEE3 4872 bytes
SHA-256: 453760a937e003f39f7d1ea258058557c8a7865d2870e94ee84baa5f26731bea
font_01_sfnt_off0000ef72.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF72 10264 bytes
SHA-256: 5e2df4a7d682edfd0f44e23101af0e56d9557b86b69170fda485d21018fb3093
font_02_sfnt_off000112a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x112A7 4324 bytes
SHA-256: 0d0f64e27578eb124b8bc81c7eceacdd166e22eddd95c81328e9fbd7de2a6333