Malicious PDF — malware analysis report

Static analysis result for SHA-256 9dd22d5e732c4d9d…

MALICIOUS

PDF

73.8 KB Created: 2021-04-24 14:14:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-26
MD5: 2e8e0e99221a96c102d369604863d505 SHA-1: 69149aebd4c94fe7bfae701d776018032ed8d2db SHA-256: 9dd22d5e732c4d9d830d5c5e361b289f899732f264c85eaa8bd98429857ab043
126 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, with one heuristic identifying it as a link farm on disposable hosting. ClamAV and an ML classifier flagged this PDF as malicious, specifically as a phishing trojan. While no scripts were extracted, the presence of many links suggests a phishing or credential harvesting attempt, likely delivered as a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://www.dgs-interparts.be/sites/default/files/7838369457.pdf In PDF document text
    • https://www.blplegal.com/sites/default/files/webform/vogelunejubujapezidugave.pdfIn PDF document text
    • https://ambrose.edu/sites/default/files/webform/21691652676.pdfIn PDF document text
    • http://portal-mysigma.com/system/files/student-proof/9555400870.pdfIn PDF document text
    • http://www.muttypawsacademy.com/sites/default/files/webform/vaccines/30199048500.pdfIn PDF document text
    • https://www.enwidth.com/sites/default/files/webform/resumes/ralivowu.pdfIn PDF document text
    • http://www.pbttphtk.gov.my/sites/default/files/webform/vojazasazobixupolaxi.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/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=is+samsung+6+series+goodPDF 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/zixulupuritijidegebi.pdfIn PDF document text
    • https://www.vub.be/sites/vub/files/webform/pagilavamuvawasaxega.pdfIn PDF document text
    • https://printandmail.princeton.edu/system/files/webform/mizol.pdfIn PDF document text
    • https://www.ice.cam.ac.uk/sites/www.ice.cam.ac.uk/files/webform/50075528518.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_off0000e4db.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4DB 5204 bytes
SHA-256: 753ce8cfafd49e0ddf0da37a1159beb59cf97ec50890388e9202a7e6c55559ee
font_01_sfnt_off0000f674.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF674 10440 bytes
SHA-256: 2f03f8832605cf529c27615f9ade6d5c26e776d55c05ccb120103de07ba5a261