Malicious PDF — malware analysis report

Static analysis result for SHA-256 8493ae44a968c821…

MALICIOUS

PDF

70.8 KB Created: 2021-10-04 01:54:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 4861df88faafe1488cb464746c106de0 SHA-1: 08083fa0ac5565a7b9c40544482bddb318defb3f SHA-256: 8493ae44a968c821a16d0cad54cee5b0448be7717998e8764caccb249f4a60a3
174 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript and numerous external links, many of which point to other PDF files hosted on disposable domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to lure the user into downloading and executing a secondary payload. The presence of JavaScript suggests an attempt to exploit vulnerabilities or perform actions beyond standard PDF rendering.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://queure.ru/uplcv?utm_term=water+after+meal+good+or+bad PDF link annotation
    • https://yuktogel.com/contents/files/81407931571.pdfIn PDF document text
    • http://quimis.net/js/ckfinder/userfiles/files/78851683370.pdfIn PDF document text
    • http://pivotal-technologies.com/userfiles/file/51835537469.pdfIn PDF document text
    • https://kpii3yaw3-7nc.com/contents/files/95702640279.pdfIn PDF document text
    • http://karaokejdi.com/ckfinder/core/connector/php/upload/files/xituxigogegeb.pdfIn PDF document text
    • http://skazka76.ru/pic/userfile/58441932730.pdfIn PDF document text
    • http://ambulatorioveterinariocigliano.com/userfiles/files/nabovuzuzub.pdfIn PDF document text
    • https://giga-tronics.com/userfiles/files/16104288967.pdfIn PDF document text
    • http://tw-sincere.com/upfiles/editor/files/nemodobagoziwepa.pdfIn PDF document text
    • http://xn--b1afklwjc5g.xn--p1ai/ckfinder/userfiles/files/nepovavetijipusitonatuna.pdfIn PDF document text
    • https://clubkdo.fr/img/pics/files/vogimanos.pdfIn PDF document text
    • https://bolahijau.com/contents/files/ninuxinopef.pdfIn PDF document text
    • http://onfireinteriors.com/userfiles/15327155683.pdfIn PDF document text
    • https://minhvuongthuphap.com/upload/ck/files/36959980854.pdfIn PDF document text
    • http://studioturina.com/userfiles/files/8571425174.pdfIn PDF document text
    • http://etalentlink.com/uploadfile/file///2021100405331751.pdfIn PDF document text
    • https://accesoriosalmayor.com/images/userfiles/file/dubuvumugivivuzovutug.pdfIn PDF document text
    • http://globalone-mould.com/gbw/fckfiles/20210906010927.pdfIn PDF document text
    • http://servicedental.it/userfiles/files/beratolomugizasudaromawi.pdfIn PDF document text
    • http://tasfor.com/files/galeria/files/95535897319.pdfIn PDF document text
    • https://bursakaynak.com/userfiles/file/rafipabonexumuzigej.pdfIn PDF document text
    • http://phunggia.biz/userfiles/file/35206154568.pdfIn PDF document text
    • https://stauber.lt/images/files/milimetek.pdfIn PDF document text
    • https://bluetact.com/ckfinder/userfiles/files/godawaxawufupefasu.pdfIn PDF document text
    • http://h-n-s.net/userfiles/file/20323214890.pdfIn PDF document text
    • http://boxshop.mn/userfiles/files/95437350645.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://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_off0000b3a9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB3A9 16632 bytes
SHA-256: ae39012a0a4154aed9022b955f63c9fa6dcf77a1c44dbdc284f3f1679d036e8b
font_01_sfnt_off0000de17.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE17 10468 bytes
SHA-256: 9948886a7b2b28b75830dc9bd85088621cdf8d7edf6a6bbd607d82ce48bd6b8c
font_02_sfnt_off0000f5b6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5B6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1