Malicious PDF — malware analysis report

Static analysis result for SHA-256 82ef4d04e772f9f9…

MALICIOUS

PDF

69.1 KB Created: 2021-04-13 06:05:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-12
MD5: a437e229d50947b98d47709c328e41b6 SHA-1: 234438412adba99fd9758f50d18d04c7ec86df1a SHA-256: 82ef4d04e772f9f9d54efee57539b0ca6f22fa6645423ab7cdcf059538e4aa45
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The sample was detected by ClamAV as Pdf.Phishing.Trojan and flagged by an ML classifier, indicating malicious intent. It contains numerous embedded URLs that form a link farm, a common technique for phishing or distributing further malware. The PDF structure and embedded content suggest it is designed to lure users into clicking these links.

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.viachristi.org/sites/default/files/webform/89070061484.pdf In PDF document text
    • https://www.termis.org/system/files/webform/manejuwavujegajejumoxak.pdfIn PDF document text
    • https://natsihwa.org.au/sites/default/files/webform/degajakuko.pdfIn PDF document text
    • https://www.osgeurope.com/sites/osg-corporate.dev/files/webform/tafunowusovuna.pdfIn PDF document text
    • http://www.sumnercountyhospital.org/sites/default/files/webform/vetasitumuwogemukuruv.pdfIn PDF document text
    • https://ambrose.edu/sites/default/files/webform/11364316539.pdfIn PDF document text
    • https://www.pharoxglobal.com/sites/default/files/webform/garuwofewitenobakufenewi.pdfIn PDF document text
    • http://www.pbttphtk.gov.my/sites/default/files/webform/vojazasazobixupolaxi.pdfIn PDF document text
    • https://web.liderpapel.com/sites/default/files/webform/53484808665.pdfIn PDF document text
    • https://www.jwico.com/sites/default/files/webform/xojisipet.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/~3/3CAf4wW3hvY/uplcv?utm_term=satanic+lust+spellPDF link annotation
    • https://www.healthdata.org/sites/default/files/resumes/sutuzosugogaw.pdfIn PDF document text
    • https://www.vub.be/sites/vub/files/webform/siwujomizawafoxewop.pdfIn PDF document text
    • https://minorsoncampus.princeton.edu/system/files/webform/45540448673.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_off0000d61f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD61F 4932 bytes
SHA-256: 4c0ae2b2794c676cc1e9236de0587d0b4878d7b7ed556dc4e9ec077981853fe6
font_01_sfnt_off0000e6f9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6F9 9608 bytes
SHA-256: 759b27beb0d8f4b868fb4c49c136bf62761ff39c68975bedc9758e6b48d2bae9