Malicious PDF — malware analysis report

Static analysis result for SHA-256 bc7b20ee17f5c13c…

MALICIOUS

PDF

81.8 KB Created: 2021-04-12 11:52:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-29
MD5: 194573db3db0e477a78648f26e196a87 SHA-1: 548f79579441417292944cbe5c9146e7954e0ccb SHA-256: bc7b20ee17f5c13c37daf6f190c189ec2064647f4143175cdc21248ce9ac2aeb
134 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains numerous external URIs, many of which are hosted on potentially disposable domains, suggesting a link farm or phishing infrastructure. The presence of a 'download button' heuristic further supports a lure-based attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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/36138637258.pdf In PDF document text
    • http://cicatsalud.com/html/sites/default/files/webform/17654710786.pdfIn PDF document text
    • http://www.pbttphtk.gov.my/sites/default/files/webform/vojazasazobixupolaxi.pdfIn PDF document text
    • https://www.jsif.org/sites/default/files/webform/94808830073.pdfIn PDF document text
    • https://www.osgeurope.com/sites/osg-corporate.dev/files/webform/14219433733.pdfIn PDF document text
    • https://www.osgeurope.com/sites/osg-corporate.dev/files/webform/keborezuvefubivuw.pdfIn PDF document text
    • http://seiary.com/sites/default/files/webform/rec/pexutagizoniged.pdfIn PDF document text
    • http://klm3fg.grhosting.cz/sites/default/files/webform/files/6948618973.pdfIn PDF document text
    • https://natsihwa.org.au/sites/default/files/webform/mufuwujaxerafesa.pdfIn PDF document text
    • http://www.guninetwork.org/system/files/webform/heirri_proposals/38059385999.pdfIn PDF document text
    • http://seiary.com/sites/default/files/webform/rec/47545977947.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/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=powerpoint+jeopardy+template+with+scPDF link annotation
    • https://printandmail.princeton.edu/system/files/webform/50156150340.pdfIn PDF document text
    • https://minorsoncampus.princeton.edu/system/files/webform/posilo.pdfIn PDF document text
    • https://www.vub.be/sites/vub/files/webform/ludazerubadariwevulefaxu.pdfIn PDF document text
    • https://www.vub.be/sites/vub/files/webform/43319512550.pdfIn PDF document text
    • https://minorsoncampus.princeton.edu/system/files/webform/libovonudipiguriteg.pdfIn PDF document text
    • https://www.ice.cam.ac.uk/sites/www.ice.cam.ac.uk/files/webform/50075528518.pdfIn PDF document text
    • https://campusrec.princeton.edu/system/files/webform/4552140304.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_off0000ff63.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF63 5584 bytes
SHA-256: 606aefe2262b2c036080326e71ce08aec422267c5026215de67e5f5c0b7eaa27
font_01_sfnt_off00011250.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11250 11744 bytes
SHA-256: 28f92423b73a3e8f31b6c69bb5e87d87fd84682ba6485fd8af6ba2c6d795abd0