Malicious PDF — malware analysis report

Static analysis result for SHA-256 fdd05541d6329ae2…

MALICIOUS

PDF

66.7 KB Created: 2021-04-14 22:57:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 57f35917aa1ce1424271c99ec3c10f6e SHA-1: 8d050846f3d6035b704e47d74ff5910391f8312d SHA-256: fdd05541d6329ae2376291e58c9731cb6cd098c9d6b4e7f2a43074057e592edf
126 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which are hosted on suspicious domains and appear to be part of a link farm. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and embedded links suggest an attempt to redirect the user to a malicious site.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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://seiary.com/sites/default/files/webform/rec/pexutagizoniged.pdf
    • https://www.a1touchsolution.nl/sites/default/files/rowiduw.pdf
    • https://ambrose.edu/sites/default/files/webform/61928937085.pdf
    • https://europa-ts.ru/sites/default/files/webform/totikejeropisatuzubafaba.pdf
    • https://ambrose.edu/sites/default/files/webform/futexapepunuvanujom.pdf
    • https://www.enwidth.com/sites/default/files/webform/resumes/21555212736.pdf
    • http://klm3fg.grhosting.cz/sites/default/files/webform/files/zavemazawutojene.pdf
    • http://russian-ice-spb.ru/sites/default/files/webform/files/loxigexaxezirizedud.pdf
    • https://natsihwa.org.au/sites/default/files/webform/17015803.pdf
    • http://www.guninetwork.org/system/files/webform/heirri_proposals/74543186253.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=thomas+nagel+what+is+it+like+to+be+a+bat+summary
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c75b.bin
7b03dc734d3141494e149be61d58fe40ed6fd76311c52a2c9de7eea12f4f30de
pdf-font-stream PDF embedded font (sfnt) at offset 0xC75B 5444 bytes
font_01_sfnt_off0000d9c7.bin
ad0a35c024dd218bd5f08f004961ac9b9748474c1a44e0de936bbb01799b0263
pdf-font-stream PDF embedded font (sfnt) at offset 0xD9C7 10852 bytes