Malicious PDF — malware analysis report

Static analysis result for SHA-256 b1617ea23370bd0e…

MALICIOUS

PDF

79.4 KB Created: 2021-09-23 02:03:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 078cf9ddbb1645f1ac0fb67fbd6e42f8 SHA-1: f4ed7822878567593bfddedb1c77234699492ec9 SHA-256: b1617ea23370bd0ecf49519bbd5a15cb3308c0058fa5013f83e940e2ab7eeded
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document exhibits characteristics of a phishing lure, specifically using a 'password-protected archive handoff' technique to conceal malicious content. It contains numerous embedded URLs, many of which point to PDF files hosted on various domains, suggesting a link farm designed to obscure the ultimate destination. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were directly extracted, the overall structure and heuristic firings point towards a phishing campaign aiming to trick users into downloading a password-protected payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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
  • Password-protected archive handoff high SE_PASSWORD_ARCHIVE_LURE
    Document gives password instructions for an archive or attachment — often used to keep payloads encrypted until after gateway scanning
  • 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://bdprescription.com/ci/userfiles/files/53963673069.pdf In PDF document text
    • http://ipsaix.com/ckeditor/ckfinder/userfiles/files/79993963799.pdfIn PDF document text
    • https://audreyheselmans.com/_files/file/puwavoxufesajixelotif.pdfIn PDF document text
    • http://emanuelarombiarchitetto.eu/userfiles/files/84718379006.pdfIn PDF document text
    • http://195exim.com/datas/files/dugixobeti.pdfIn PDF document text
    • http://gonganmi.com/userfiles/file/29222821138.pdfIn PDF document text
    • https://valve-toho.com/userfiles/file/kepazikipobagugijej.pdfIn PDF document text
    • https://ripedzn.com/app/webroot/files/fckeditor/file/sugizexitupobetumiludut.pdfIn PDF document text
    • https://thehouseproduction.net/file/58763853104.pdfIn PDF document text
    • http://2015.letnifestiwal.pl/ckfinder/userfiles/files/82113625991.pdfIn PDF document text
    • https://telewebmarketing.com/FCKeditor/file/pidowugulub.pdfIn PDF document text
    • https://jpjplumbingandheating.com/FCKeditor/file/vubepuseteku.pdfIn PDF document text
    • https://ntct-dz.com/ckfinder/userfiles/files/19282295483.pdfIn PDF document text
    • http://cohn-vossen.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613718556d8d3---84759109506.pdfIn PDF document text
    • http://fastcredit.ge/userfiles/file/216263669.pdfIn PDF document text
    • http://softwaretesting.kr/club/data/userfiles/file/20210912042051.pdfIn PDF document text
    • http://heninrealty.com/userfiles/files/84536642012.pdfIn PDF document text
    • http://cn-polylysine.com/d/files/pesanogimaxifiguji.pdfIn PDF document text
    • http://hoya889.com/upfile/files/20210923045946.pdfIn PDF document text
    • http://abwnickersonplaza.com/uploads/files/xedavenutamudewe.pdfIn PDF document text
    • http://henzefashion.com/userfiles/file/75452401334.pdfIn PDF document text
    • http://www.alfainstal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/161313f4d01124---xugilujajexikadixur.pdfIn PDF document text
    • https://thanaclusterwestgate.leaddeehub.com/userfiles/files/gitoja.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=cara+membuka+file+bin+di+hp+androidPDF link annotation
    • 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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d170.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD170 17620 bytes
SHA-256: 76784a33749c5db639e795f6691d4231474ecef382972390ca26695f2ac6a6c7
font_01_sfnt_off0000ffb2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFFB2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000117c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x117C9 10860 bytes
SHA-256: 65f6469835941742b9a2efa0efa76222a1211806295f9d52e82d1b12c9e441db