Malicious PDF — malware analysis report

Static analysis result for SHA-256 f641e524b61b7aaf…

MALICIOUS

PDF

86.4 KB Created: 2021-09-10 19:50:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 26883191c7e75dd50ff1d2e57ac850e3 SHA-1: fbc13fd4ce1b9328de13e56f87861746bfbc3727 SHA-256: f641e524b61b7aaf40ae27e4af1ec6f3e4e4befe5a8281a8610462eaaa4dc638
206 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains multiple links to external PDFs hosted on disposable domains, a common tactic to evade detection by security gateways. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a deliberate attempt to create a link farm on low-reputation hosting. ClamAV detection and ML classification confirm the malicious nature of the file, likely serving as a downloader or part of a phishing campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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.
  • 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 http://lamarchesainterita.be/lamarchesainterita/imgdb/news/files/zejosolanixumadetebos.pdf In PDF document text
    • https://tatsolarlight.com/uploads/files/koxemifikes.pdfIn PDF document text
    • https://westhigienia.hu/editor_up/56522334828.pdfIn PDF document text
    • http://altera.ukrstroyka.com/content/xuploadimages/file/84479936361.pdfIn PDF document text
    • http://sentai.cc/data/file/20210909_001002_713.pdfIn PDF document text
    • http://24x7taazasamachar.com/assets/ckfinder/core/connector/php/uploads/files/wedironipiwivokuwikafim.pdfIn PDF document text
    • https://www.highettmetal.com.au/application/third_party/ckfinder/userfiles/files/69425900622.pdfIn PDF document text
    • http://waterlootour.com/FileData/ckfinder/files/20210904_89035A7F35D61888.pdfIn PDF document text
    • https://lorenzonimmigrationlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/161386b76cd6fa---7924698387.pdfIn PDF document text
    • https://rh4-h1tapi-turbo.com/contents/files/17945295695.pdfIn PDF document text
    • https://ost-fogging.com/upload/files/41919684541.pdfIn PDF document text
    • http://issaproject.com/app/views/panel/ckfinder/userfiles/files/nezezipit.pdfIn PDF document text
    • http://raylutickenterprises.com/userfiles/files/44825732118.pdfIn PDF document text
    • http://veterinarioassociatopacinidallatorre.eu/userfiles/files/15587390707.pdfIn PDF document text
    • http://www.ximangsongthao.com.vn/app/webroot/uploads/files/17802116307.pdfIn PDF document text
    • http://autohondl.cz/userfiles/file/magivax.pdfIn PDF document text
    • http://chinastom.ru/userfiles/file/31895884134.pdfIn PDF document text
    • http://status.cz/UserFiles/File/16572673951.pdfIn PDF document text
    • https://binarbaidfabrication.com/public_html/userfiles/file/fepaferagotizoripapa.pdfIn PDF document text
    • http://lapenya.cat/imgjovesnaves/file/sewit.pdfIn PDF document text
    • https://jiu-hang.com/upfiles/editor/files/32814613329.pdfIn PDF document text
    • https://academiapreprod.riportico.com/userfiles/files/fazirujunebonatomuwa.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=buscador+de+aplicaciones+para+android+gratisPDF 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_off0000e7ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7CE 10840 bytes
SHA-256: 6f6bcd255b961c5b0d95a7fde31512952c6005e79f602c3e7aecccd3b194a061
font_01_sfnt_off000100bf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100BF 19256 bytes
SHA-256: 8d6f1362e098d76809732394c45095b38dfb1b10aaee61ff64098f183ff9da96
font_02_sfnt_off000131c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x131C9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1