Malicious PDF — malware analysis report

Static analysis result for SHA-256 8757a5b2d0a4aa5e…

MALICIOUS

PDF

86.0 KB Created: 2021-04-10 16:29:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-29
MD5: 47c6b14cbd62d234c0064ca2f0509ef9 SHA-1: e2a4403803411e8af7d5c15c2ccff307113a7525 SHA-256: 8757a5b2d0a4aa5ec50901547b9c34fd12706a3bb01a3c57bb6f697c6ceca4a2
126 Risk Score

Malware Insights

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

This PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to link farms or disposable hosting, suggesting an attempt to redirect users to malicious sites. The document body, though heavily obfuscated, contains text related to 'Estudios biblicos para jovenes pdf', likely a lure to attract victims.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://oaklandchildcare.org/sites/default/files/webform/34869944823.pdf In PDF document text
    • http://www.pacificsportfraservalley.com/sites/default/files/webform/pulipalukegibivep.pdfIn PDF document text
    • http://www.guninetwork.org/system/files/webform/heirri_proposals/rarapenebeku.pdfIn PDF document text
    • http://klm3fg.grhosting.cz/sites/default/files/webform/files/56601188302.pdfIn PDF document text
    • https://www.telluridescience.org/sites/default/files/tstc-applications/kuvusuwube.pdfIn PDF document text
    • https://ambrose.edu/sites/default/files/webform/46846662681.pdfIn PDF document text
    • http://www.friendlycc.com/sites/default/files/webform/tojatovovezugunubi.pdfIn PDF document text
    • http://www.sumnercountyhospital.org/sites/default/files/webform/sixativitav.pdfIn PDF document text
    • http://www.pbttphtk.gov.my/sites/default/files/webform/88462653206.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/~3/3CAf4wW3hvY/uplcv?utm_term=estudios+biblicos+para+jovenes+pdfPDF link annotation
    • https://lib.asu.edu/system/files/webform/liwubuwivak.pdfIn PDF document text
    • https://gradfutures.princeton.edu/system/files/webform/ninavixokamorul.pdfIn PDF document text
    • https://drones.princeton.edu/system/files/webform/66931006591.pdfIn PDF document text
    • https://campusrec.princeton.edu/system/files/webform/34970544405.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_off000101da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x101DA 5264 bytes
SHA-256: e4b8a46070869e47df3c0631f0d9e47ea7bc67e0a33a6cdeb02a0fb1b0b6088d
font_01_sfnt_off000113cf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x113CF 12620 bytes
SHA-256: 23bf4925ce99b9d8ff06185858ab8ff09d7473b782e41fa711c6161a8cab17b1
font_02_sfnt_off00013b88.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13B88 4324 bytes
SHA-256: 9f355172d696dda274cac500966718f112ce76951f19577ac4888987ea6471b2