Malicious PDF — malware analysis report

Static analysis result for SHA-256 ac5ef4be6693d0be…

MALICIOUS

PDF

81.4 KB Created: 2021-09-17 07:55:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: fc9f2206c82231fd57153e77265fcec7 SHA-1: dec5754396b547189d23c22ad09c6edc91642e90 SHA-256: ac5ef4be6693d0becd95e863988ab3e8bd036f2eab77015dd41ad804a0fecfac
146 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous embedded URIs, including one pointing to a raw IP address, suggesting it functions as a link farm or redirects users to malicious sites. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' further supports this, indicating the PDF is designed to host many links on disposable domains.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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
  • 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://modra-skola.cz/userfiles/file/7664702738.pdf In PDF document text
    • http://cegled.varosom.hu/userfiles/files/rimivopo.pdfIn PDF document text
    • http://korea-seals.com/ckfinder/userfiles/files/39511596686.pdfIn PDF document text
    • http://gps-tw.com/CKEdit/upload/files/vazuni.pdfIn PDF document text
    • http://lafenicealcamo.it/userfiles/files/vemilekexiwerubizoji.pdfIn PDF document text
    • http://jr.ac.th/ckfinder/userfiles/files/5349424293.pdfIn PDF document text
    • https://chorland-dining.com/webroot/editor-uploads/files/68285879744.pdfIn PDF document text
    • http://primeasset.hu/fileok/file/voxajuta.pdfIn PDF document text
    • https://srccaa.bdbabymart.com/app/webroot/ckfinder/userfiles/files/96349065648.pdfIn PDF document text
    • https://activsport.ro/userfiles/file/jagebirumukefitilezo.pdfIn PDF document text
    • http://www.fashiongale.ro/userfiles/files/19810000152.pdfIn PDF document text
    • http://140.121.125.49/ckfinder/userfiles/files/20210912_182217.pdfPDF link annotation
    • http://damosushipleasanthill.com/uploads/files/mozefi.pdfIn PDF document text
    • https://grouptm2.com/contents/files/wodipodamurigep.pdfIn PDF document text
    • https://atl-50.com/files/file/17167934846.pdfIn PDF document text
    • https://www.sharpeningfactory.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613fa466f1ffc---51516763327.pdfIn PDF document text
    • https://bestcaps99.com/ckfinder/userfiles/files/vavufujuv.pdfIn PDF document text
    • http://mobilahomedesign.com/userfiles/files/lajoresuvasarofoxup.pdfIn PDF document text
    • http://teplorium.su/userfiles/file/sozikebademipalutuviker.pdfIn PDF document text
    • http://hosungtour.com/FileData/ckfinder/files/20210902_30DC3FA5EE4F3D89.pdfIn PDF document text
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16134bcbfab814---visaganulevomubu.pdfIn PDF document text
    • http://laserbeautymachine.net/d/files/14859905082.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=transformers+comics+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_off0000dbac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBAC 10600 bytes
SHA-256: 04e11c6c9b53ea95c0dd694a20ee7ea1e846dd8b79caf2b4a08c5303289634ae
font_01_sfnt_off0000f3d7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3D7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010be9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10BE9 17192 bytes
SHA-256: 2f934c1edf827a09053f8f56f70718492c5a4e2c5b7caf80dd12b8694f8b550c