Malicious PDF — malware analysis report

Static analysis result for SHA-256 448aa21189b421f4…

MALICIOUS

PDF

68.1 KB Created: 2021-04-22 16:23:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-26
MD5: 69e8cbc6a0de1b5063dc8d77797938dd SHA-1: d648b2424932dd7397d42091c55265d6995f8f7b SHA-256: 448aa21189b421f4a331304e8dbc2dd663cdad294076147716bb2fddc97a9174
126 Risk Score

Malware Insights

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

The sample is a PDF file flagged as malicious by ClamAV and an ML classifier. It contains numerous embedded URLs, with one pointing to a suspicious domain ('klm3fg.grhosting.cz') that is identified as a link farm. The PDF structure and the presence of multiple links suggest an attempt to direct users to potentially harmful content, consistent with phishing or malware delivery. No scripts were extracted, but the overall structure and URL analysis indicate a malicious intent.

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://klm3fg.grhosting.cz/sites/default/files/webform/files/15194676649.pdf In PDF document text
    • https://ambrose.edu/sites/default/files/webform/padubomi.pdfIn PDF document text
    • https://www.jwico.com/sites/default/files/webform/vuvosiritixulufanili.pdfIn PDF document text
    • https://www.enwidth.com/sites/default/files/webform/resumes/sojinikud.pdfIn PDF document text
    • https://architecturaldesigninc.com/sites/default/files/sujuxot.pdfIn PDF document text
    • https://grossenbacher.co.nz/en/system/files/avoidance-training-certificates/xetomaroronep.pdfIn PDF document text
    • http://www.birdlifebotswana.org.bw/sites/default/files/webform/sightings-sketches/beporu.pdfIn PDF document text
    • https://www.uts.cw/sites/default/files/webform/50818196885.pdfIn PDF document text
    • https://www.pharoxglobal.com/sites/default/files/webform/balulata.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/FevRqgeaUVY/uplcv?utm_term=masterbuilt+propane+smoker+coverPDF link annotation
    • https://umatter.princeton.edu/system/files/webform/requests/roporopapoviz.pdfIn PDF document text
    • https://campusrec.princeton.edu/system/files/webform/jelozubunumi.pdfIn PDF document text
    • https://www.ice.cam.ac.uk/sites/www.ice.cam.ac.uk/files/webform/10713621665.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_off0000cc88.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC88 5348 bytes
SHA-256: ac39c90885a482449a4a9afa7d569fad64f3edb4e0a7110f49c1e4d67d04790b
font_01_sfnt_off0000deb2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDEB2 10972 bytes
SHA-256: 783b35fccf97a01ed40f4b01ece1dd69ceb5020c5513893ec0ea7498bb8fa728

Open this report in the interactive analyzer, or submit your own file for analysis.