Malicious PDF — malware analysis report

Static analysis result for SHA-256 87b5995ddbc38be0…

MALICIOUS

PDF

79.9 KB Created: 2021-09-20 00:04:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 420fa57264060e50830ba7c505325e60 SHA-1: 1f359489a70d57d4a0cca0336e65556f486351e8 SHA-256: 87b5995ddbc38be0088a43919276b0f6d4cac32df9a7d23ff5cc31aa069580b5
146 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to other PDF files hosted on potentially compromised websites, indicating a link farm or redirection mechanism. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' further supports the analysis that this PDF is part of a scheme to distribute malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Clickable URI points to raw IP address medium PDF_URI_IP_LITERAL
    PDF contains a clickable HTTP(S) action whose host is a literal IPv4 address. Legitimate documents normally link to named domains; raw-IP destinations are common in disposable phishing and malware-delivery infrastructure.
  • 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://evo-models.com/uploads/userfiles/files/29733024561.pdf In PDF document text
    • http://share-world.tw/userfiles/file/dufawaxinojapuniletutuzes.pdfIn PDF document text
    • http://catherine-massage.com/ckfinder/userfiles/files/8709996618.pdfIn PDF document text
    • https://mcq-exambd.bdbabymart.com/app/webroot/ckfinder/userfiles/files/76951165526.pdfIn PDF document text
    • http://casaatlantida.com/userfiles/file///wokuxafure.pdfIn PDF document text
    • https://akemi.ro/hirek/file/66424488949.pdfIn PDF document text
    • http://www.pattyn360.com/upload/forum/files/wixaputuwo.pdfIn PDF document text
    • https://kolkatanagariksammelan.org/ckfinder/userfiles/files/39837673732.pdfIn PDF document text
    • https://rais.bg/uploads/file/18630915977.pdfIn PDF document text
    • https://matricula.arendic.cl/files/73940106738.pdfIn PDF document text
    • https://montpellier-business-plan.com/mbp/upload/images/images/upload/ckfinder/samixet.pdfIn PDF document text
    • https://ibextrail.com/editor-images/biwobitumerolunomaban.pdfIn PDF document text
    • http://bscsaoner.in/ckfinder/userfiles/files/53384078559.pdfIn PDF document text
    • https://thesmithgrouphouston.com/wp-content/plugins/super-forms/uploads/php/files/5b7722678c7274c244613c0f61457ea2/gikevatapis.pdfIn PDF document text
    • https://mbzl-pro.xyz/web/img/podborky/files/47096213026.pdfIn PDF document text
    • https://shiksha24.com/userfiles/files/zajivegakotutazowu.pdfIn PDF document text
    • https://bd-sokolovska.eu/userfiles/file/dazorositesalagezijisadog.pdfIn PDF document text
    • https://haidangpc.com/contents/files/zuxodez.pdfIn PDF document text
    • http://ausafe.net/images/art/files/jegidexifetofadagegof.pdfIn PDF document text
    • http://solartgaleria.hu/images/file/19676493580.pdfIn PDF document text
    • http://www.skupp.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1614639d3e4c61---36131102956.pdfIn PDF document text
    • http://www.nena-artspace.com/ckfinder/userfiles/files/gumutagukat.pdfIn PDF document text
    • http://79.170.40.182/boothtastic.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612fce0023f76---vifusufojitijiget.pdfPDF link annotation
    • https://titishop.co/upload/files/gesikeve.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=blueprint+mcat+books+pdfPDF 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_off0000d21e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD21E 11168 bytes
SHA-256: 0233fafdf79dee7c9d76c8250dca3f426098a90ed8cbabefa2607c5916a45bc3
font_01_sfnt_off0000ec00.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC00 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010412.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10412 17796 bytes
SHA-256: 15e0e7ac111779875d092cf4b8957d7a41bddaa920f64e95bcdfffe5f848a558