Malicious PDF — malware analysis report

Static analysis result for SHA-256 c43dd53b8e0a142c…

MALICIOUS

PDF

70.3 KB Created: 2021-09-26 13:57:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 9132cf3ad962491e9cd2e6ac8e2f572d SHA-1: 68c9a33073bead6afb5ad150b923052d5f736a44 SHA-256: c43dd53b8e0a142cc83a5a958ed7d372b8bc6066dedb011c86bbdac341ad1f39
166 Risk Score

Malware Insights

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

The PDF document contains a high-severity heuristic firing for a random URL link, pointing to a suspicious PDF file. ClamAV also detected this file as 'Pdf.Phishing.Trojan'. The ML classifier output of 0.997504 further supports its malicious nature. The primary attack pattern involves directing the user to download a secondary malicious payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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
  • PDF link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://havadisname.com/upload/ckfinder/files/22681476643.pdf In PDF document text
    • http://gruaszarate.com/ckfinder/userfiles/files/busanalavakasu.pdfIn PDF document text
    • https://vinocastillo.hu/editor_up/fagoponuvokesotev.pdfIn PDF document text
    • http://klhl.com/userfiles/file/bipubegijifepaxulupeme.pdfIn PDF document text
    • http://ytovietnam.net/ckfinder/userfiles/files/52089274419.pdfIn PDF document text
    • http://watch62.ru/files/files/ruzufixopomun.pdfIn PDF document text
    • http://suriyedostlukdernegi.org/image/files/dovadukorajuvisukav.pdfIn PDF document text
    • http://kaies.cn/upfiles/210915212036647865yvtnnt.pdfIn PDF document text
    • https://pcparts.fr/ckfinder/userfiles/files/45060498276.pdfIn PDF document text
    • http://dgxzz.com/uploadfile/file/wuselim.pdfIn PDF document text
    • https://www.mybizwebsites.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614fa87f6a171---22756917492.pdfIn PDF document text
    • http://residenceraffaellotorino.com/userfiles/files/milubawovijeneju.pdfIn PDF document text
    • http://daiichilogistics.com/uploads/news_file/texefofapefapapoxiwepuve.pdfIn PDF document text
    • http://carraracucinecomponibilitrapani.it/userfiles/files/pexixej.pdfIn PDF document text
    • http://erex.hu/upload/file/4637603050.pdfIn PDF document text
    • http://tg-focus.ru/userfiles/files/69275802301.pdfIn PDF document text
    • http://jeykrishnaclub.com/images/file/lupukubezevusubatuvaxuzi.pdfIn PDF document text
    • http://myjobcareer.net/userfiles/file/2021092614572973499.pdfIn PDF document text
    • http://kasintorn.com/images/upload/files/2490121513.pdfIn PDF document text
    • https://digireg.cz/upload/vaxinerivirabogukoraj.pdfIn PDF document text
    • http://onestep-tokyo.com/userfiles/file/63488499222.pdfIn PDF document text
    • https://araprinter.com/ckfinder/userfiles/files/55967636557.pdfIn PDF document text
    • http://fese.in/ienupdimages/images/files/zokudojevafu.pdfIn PDF document text
    • http://jnmindia.com/outscapes/admin/ckeditor/uploads/ck/files/2041077424.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=final+fantasy+3+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_off0000b2a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB2A7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cab9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCAB9 15992 bytes
SHA-256: d3a760809dc32bd7af67c7f95bbceb7df8e296a4cd927828a01ffe16d59257cf
font_02_sfnt_off0000f377.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF377 10476 bytes
SHA-256: a2348340bc16b45e633a83a07abb06bd3c49d86162ca8e74d5d0f21b036317b5