Malicious PDF — malware analysis report

Static analysis result for SHA-256 2943b4482b78ea76…

MALICIOUS

PDF

70.2 KB Created: 2021-04-22 08:46:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-29
MD5: 0cf37f39a3a8b72ebb13c9451c3d305f SHA-1: 17a8ba066e1e5600677246bd06a518006f66daf6 SHA-256: 2943b4482b78ea769decd63961a2d9ae737ba385c403a09588145c250eb10824
126 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to disposable domains and are structured as link farms, indicating a phishing or malicious redirection attempt. The ML classifier and ClamAV detection strongly suggest malicious content. While no scripts were explicitly extracted, the PDF structure and heuristic firings point towards a phishing lure, likely intended to deliver a secondary payload or redirect to a malicious site.

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://ambrose.edu/sites/default/files/webform/rebunedirewe.pdf In PDF document text
    • https://www.mothercare.ro/sites/default/files/webform/resumes/95866450710.pdfIn PDF document text
    • http://oaklandchildcare.org/sites/default/files/webform/55178968397.pdfIn PDF document text
    • http://www.sumnercountyhospital.org/sites/default/files/webform/72664382884.pdfIn PDF document text
    • https://www.osgeurope.com/sites/osg-corporate.dev/files/webform/nutuzisujobipusife.pdfIn PDF document text
    • http://russian-ice-spb.ru/sites/default/files/webform/files/69309865186.pdfIn PDF document text
    • https://www.osgeurope.com/sites/osg-corporate.dev/files/webform/povufukawonafano.pdfIn PDF document text
    • https://www.jwico.com/sites/default/files/webform/koxajupenukolipidawikopi.pdfIn PDF document text
    • https://www.ofalloncasting.com/sites/default/files/webform/tirudekamevajoluzagobumi.pdfIn PDF document text
    • http://klm3fg.grhosting.cz/sites/default/files/webform/files/zavemazawutojene.pdfIn PDF document text
    • https://www.woonsocketri.org/system/temporary/webform/makepepatamizozixijefawop.pdfIn PDF document text
    • https://ambrose.edu/sites/default/files/webform/93854264345.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/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=wu+tang+show+on+netflixPDF link annotation
    • https://community.princeton.edu/system/files/webform/jidubiziro.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_off0000c90c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC90C 4988 bytes
SHA-256: 5f649c6f9895986ab0603765a8d53ae1ea05e70f732ba2a1080d8300e0642a9d
font_01_sfnt_off0000da21.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA21 10164 bytes
SHA-256: 208c79dc7cfc20061fa0f905da6d59ddb87fdd06be90a30f20e2ef6c8d07f0ac
font_02_sfnt_off0000fcc8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFCC8 4324 bytes
SHA-256: 9f355172d696dda274cac500966718f112ce76951f19577ac4888987ea6471b2