Malicious PDF — malware analysis report

Static analysis result for SHA-256 23bda1e9317be004…

MALICIOUS

PDF

88.7 KB Created: 2021-04-14 06:33:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-29
MD5: 3fba39bd8b22babc354c31194abdf4ba SHA-1: 77abd5146254402601cae125a65508a150ae0fc6 SHA-256: 23bda1e9317be0048d11dd8c53586f3fdd9b10610370d21a0a14b4b60f88c83c
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 a link farm, a common tactic for phishing or distributing further malware. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were directly extracted, the PDF structure and URL patterns suggest it's designed to redirect users to malicious content, likely as a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://aboss.by/sites/default/files/webform/10891008032.pdf In PDF document text
    • http://spotlight-sites.com/sites/default/files/webform/wokasonexigugeb.pdfIn PDF document text
    • https://www.newburghgroup.com/sites/default/files/webform/resumes/tikijoti.pdfIn PDF document text
    • https://grossenbacher.co.nz/en/system/files/avoidance-training-certificates/tojawi.pdfIn PDF document text
    • http://www.guninetwork.org/system/files/webform/heirri_proposals/wozat.pdfIn PDF document text
    • http://cicatsalud.com/html/sites/default/files/webform/bulurifabisiwotubavigivos.pdfIn PDF document text
    • https://www.newburghgroup.com/sites/default/files/webform/resumes/41319995155.pdfIn PDF document text
    • https://www.dgs-interparts.be/sites/default/files/68462010443.pdfIn PDF document text
    • https://architecturaldesigninc.com/sites/default/files/36110977311.pdfIn PDF document text
    • https://www.jsif.org/sites/default/files/webform/54003515034.pdfIn PDF document text
    • https://www.uts.cw/sites/default/files/webform/xewaz.pdfIn PDF document text
    • https://www.mainephilanthropy.org/sites/default/files/5296457674.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/fzgW7-mxBc0/uplcv?utm_term=beginning+cosmetic+chemistry+3rd+ediPDF link annotation
    • https://www.ice.cam.ac.uk/sites/www.ice.cam.ac.uk/files/webform/wosevojowavinojefe.pdfIn PDF document text
    • https://printandmail.princeton.edu/system/files/webform/98467125123.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_off00010eb9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10EB9 5212 bytes
SHA-256: 3e8bc2f5c23a7f3197679908b9719c2800179c571e2440640b165bd074271991
font_01_sfnt_off00012045.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12045 11728 bytes
SHA-256: 8b97334921ea889211aec79f58ae91b3008c475e6af15185a6ae5bd99ccba34c
font_02_sfnt_off000147d9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x147D9 4324 bytes
SHA-256: 4fcfa7c68d76e23b667942a3ac892d2d5d88346478daafc61479ad4df4af3dd3