Malicious PDF — malware analysis report

Static analysis result for SHA-256 4b762505388b0553…

MALICIOUS

PDF

73.7 KB Created: 2021-09-14 13:48:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 09d87e09490eda26c46466a67ba62f35 SHA-1: 229aa36da5fa5f939e2bb285e8e93b88641331ba SHA-256: 4b762505388b05530fe4f71ca0a638ebd5e67cd9ac9ff69edb43742887632658
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It contains numerous embedded URLs, many of which point to compromised CMS upload directories or are hosted on disposable domains, suggesting a link farm designed to redirect users to malicious content. The document body is heavily obfuscated and unreadable, providing no direct user-facing lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://parfumerieindex.nl/images/uploads/24677087254.pdf In PDF document text
    • https://confidence-ist.mktechsol.com/ckfinder/userfiles/files/56973638975.pdfIn PDF document text
    • https://www.nobleorthodontic.com/wp-content/plugins/super-forms/uploads/php/files/798a5bb018a51aee501ccdddb9b0e686/wowegoguwuvujemawuju.pdfIn PDF document text
    • http://combatkuntao.com/ckeditor/ckfinder/userfiles/files/87147673615.pdfIn PDF document text
    • http://xn--80aafkatcapceshpicpg3h.xn--p1ai/pict/file/12367263199.pdfIn PDF document text
    • https://www.rougeindigo.com/ckfinder/userfiles/files/rojisi.pdfIn PDF document text
    • https://adian.eus/files/galeria/files/fawazinazuxofonago.pdfIn PDF document text
    • https://www.golddustdental.com/wp-content/plugins/formcraft/file-upload/server/content/files/161382cd05f6f5---88899831781.pdfIn PDF document text
    • http://lexxyin.net/files/fckeditor/file/12601536581.pdfIn PDF document text
    • https://supermagnum-bg.com/ckfinder/userfiles/files/52332457946.pdfIn PDF document text
    • http://ndt-ultratech.com/files/48291133427.pdfIn PDF document text
    • http://automsystem.com/UploadFile/file/20210909014910447.pdfIn PDF document text
    • http://s4l.vn/storage/ckfinder/files/kilofize.pdfIn PDF document text
    • https://www.brunosistemi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613215a070023---tomomotogigeperekot.pdfIn PDF document text
    • https://hondaotohaiphong.vn/upload/files/2492492515.pdfIn PDF document text
    • https://cuatudongnhatrang.com/uploads/files/60738819999.pdfIn PDF document text
    • https://aayams.com/userfiles/file/21366024261.pdfIn PDF document text
    • http://appli-veolia.net/ckfinder/userfiles/files/67486592923.pdfIn PDF document text
    • https://rowsontw.com/shopadmin/upload/files/wazojamepu.pdfIn PDF document text
    • http://swatimishra.in/uploaded_files/userfiles/files/50370869121.pdfIn PDF document text
    • https://biocoils.com/img/file/29482173093.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=resso+pro+mod+apkPDF 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_off0000be0e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBE0E 10352 bytes
SHA-256: 069966d4bc9651e6291ae3e66e94355b4f8565265556ffd0235d4985437bd982
font_01_sfnt_off0000d572.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD572 17312 bytes
SHA-256: 881d27a657d17dcb6050cd420fc7ae8460984afae502a102eff88be657ceb4b1
font_02_sfnt_off0001016b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1016B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1