Malicious PDF — malware analysis report

Static analysis result for SHA-256 a17eb4204e2ab49a…

MALICIOUS

PDF

69.7 KB Created: 2021-04-26 23:02:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-29
MD5: 555c72d78b46941ad893c0f73df17f0c SHA-1: 2b0aca0fc72e823b5a12036c9e5d21b6a11047f2 SHA-256: a17eb4204e2ab49aef3d4bce05722a990fd39c0491bf77ab99fa7bcdde2727d3
126 Risk Score

Malware Insights

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

The sample is a PDF file flagged by ML classifiers and ClamAV as malicious. It contains numerous embedded URLs pointing to various domains, many of which appear to be part of a link farm designed to obscure the ultimate destination. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic specifically calls out this behavior, suggesting a phishing or malware distribution attempt.

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://web.liderpapel.com/sites/default/files/webform/xikamiwaboloz.pdf In PDF document text
    • http://cicatsalud.com/html/sites/default/files/webform/17654710786.pdfIn PDF document text
    • http://klm3fg.grhosting.cz/sites/default/files/webform/files/6948618973.pdfIn PDF document text
    • https://www.newburghgroup.com/sites/default/files/webform/resumes/woxofenobe.pdfIn PDF document text
    • http://pilgrimland.com/sites/default/files/webform/resume-uploads/69774832497.pdfIn PDF document text
    • https://natsihwa.org.au/sites/default/files/webform/degajakuko.pdfIn PDF document text
    • https://www.visitsavannah.com/sites/default/files/webform/71260674720.pdfIn PDF document text
    • https://extranet.blanchisserie-toulousaine-de-sante.com/sites/extranet.blanchisserie-toulousaine-de-sante.com/files/documents/justificatifs/goxara.pdfIn PDF document text
    • http://www.muttypawsacademy.com/sites/default/files/webform/vaccines/nojezajewi.pdfIn PDF document text
    • https://www.uts.cw/sites/default/files/webform/bofuwidesuxugebogaxa.pdfIn PDF document text
    • https://www.a1touchsolution.nl/sites/default/files/tarutemivejumariwara.pdfIn PDF document text
    • http://klm3fg.grhosting.cz/sites/default/files/webform/files/wajuso.pdfIn PDF document text
    • https://www.mainephilanthropy.org/sites/default/files/30695142459.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/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=what+is+the+scottish+rite+of+freemasonryPDF link annotation
    • https://thesanfordschool.asu.edu/sites/default/files/webform/20850651402.pdfIn PDF document text
    • https://printandmail.princeton.edu/system/files/webform/60959229638.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_off0000d403.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD403 5204 bytes
SHA-256: 201b24d85cb245eeb8b7df078c5a248092dad2db9291ceb053bed5e3574c0284
font_01_sfnt_off0000e59e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE59E 10660 bytes
SHA-256: 0baedd3bfcd98524c3272e7786fbf7e6f8ff257447c0155c2fa0fe74f971265b