Malicious PDF — malware analysis report

Static analysis result for SHA-256 f43ddf49228e2c2e…

MALICIOUS

PDF

65.5 KB Created: 2021-04-09 11:54:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-29
MD5: 2e9d659d961dcdd0f5aa14b773d77620 SHA-1: 0329bcab3800dfa63003ea6bbe3c3ef8f2a6acec SHA-256: f43ddf49228e2c2e701f836964e86c20bb12a3bfeaa140f87b8f13b89aa7cab0
126 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. The heuristics indicate it functions as a link farm, directing users to multiple unknown URLs disguised as legitimate resources. While no scripts were explicitly extracted, the nature of the PDF and the presence of numerous embedded URLs suggest an attempt to redirect the user to a malicious site for further exploitation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://www.jsif.org/sites/default/files/webform/moridiwivomepagaduso.pdf In PDF document text
    • https://www.natsihwa.org.au/sites/default/files/webform/bukitonixoravutewoluba.pdfIn PDF document text
    • http://seiary.com/sites/default/files/webform/rec/47545977947.pdfIn PDF document text
    • https://www.pharoxglobal.com/sites/default/files/webform/garuwofewitenobakufenewi.pdfIn PDF document text
    • http://portal-mysigma.com/system/files/student-proof/wofofokarawivuboniju.pdfIn PDF document text
    • https://www.ofalloncasting.com/sites/default/files/webform/wibojamivumararevede.pdfIn PDF document text
    • http://www.grotekeukens.be/sites/default/files/webform/gmawards2018/30150103061.pdfIn PDF document text
    • https://www.ofalloncasting.com/sites/default/files/webform/gegemapoxazokex.pdfIn PDF document text
    • http://www.guninetwork.org/system/files/webform/heirri_proposals/35039450578.pdfIn PDF document text
    • https://www.natsihwa.org.au/sites/default/files/webform/72917344941.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/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=bazel+tutorial+pdfPDF link annotation
    • https://ec.europa.eu/eip/agriculture/sites/default/files/webform/77241298986.pdfIn PDF document text
    • https://minorsoncampus.princeton.edu/system/files/webform/45540448673.pdfIn PDF document text
    • https://community.princeton.edu/system/files/webform/26098210740.pdfIn PDF document text
    • https://ec.europa.eu/eip/agriculture/sites/default/files/webform/vojevo.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_off0000c40e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC40E 4956 bytes
SHA-256: a1f47bee9a40932da524fe87ba109a1e3c45b04efdc1d57365370f001a9c6263
font_01_sfnt_off0000d506.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD506 10620 bytes
SHA-256: e0dde5b40e390cd716a3865762c85cbce7d8ab0e498853d387b71d05a55cf6dc