Malicious PDF — malware analysis report

Static analysis result for SHA-256 e99c5921e55c86b9…

MALICIOUS

PDF

85.1 KB Created: 2021-09-14 15:34:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 8bf43121262c6a9960c6e16063a307ee SHA-1: a834c85ba685f6631a80d91dba5ffea1e973e5ac SHA-256: e99c5921e55c86b9b3123a1f7126f10c48098a862774648bc8fcfa8891bca102
266 Risk Score

Malware Insights

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

This PDF document exhibits multiple high-risk social engineering lures, including a request for recovery secrets and a prompt to install browser extensions. The presence of numerous embedded URLs, many pointing to PDF files on unknown domains, suggests a link farm or distribution mechanism for further malicious content. While no scripts were directly extracted, the PDF structure and embedded URLs are indicative of a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9961

Heuristics 8

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Recovery secret / private key request critical SE_SECRET_RECOVERY_LURE
    Document requests recovery phrases, private keys, backup codes, or saved passwords. Requests for these secrets in a document are high-risk.
  • 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
  • Browser extension / update installation lure high SE_BROWSER_INSTALL_LURE
    Document tells the user to install a browser extension, plugin, viewer, or browser update to view content — a common social-engineering path for credential theft and malware installation
  • 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://nnkcreations.com/userfiles/file/larexumobif.pdf In PDF document text
    • http://thekitchendesignstudio.org/uploads/files/81274922823.pdfIn PDF document text
    • http://tctrack.vn/images/newtech/files/94753539622.pdfIn PDF document text
    • http://teamhead.net/userfiles/file/95384309138.pdfIn PDF document text
    • https://reitinguok.lt/userfiles/file/nujukupevasaluxusagi.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e03afa8c91---19217011848.pdfIn PDF document text
    • http://bladensburg.abwingsmd.com/uploads/files/74603104424.pdfIn PDF document text
    • http://changjiujz.com/uploads/files/202109042107562064.pdfIn PDF document text
    • http://epmresearch.org/userfiles/files/65367859521.pdfIn PDF document text
    • https://vitanov.rs/files/36252463317.pdfIn PDF document text
    • https://www.rapn.ru/ckfinder/userfiles/files/23194367090.pdfIn PDF document text
    • http://carrasvilla.es/uploads/files/kuwovakinuwoxoxovonoxe.pdfIn PDF document text
    • http://christopherspubandgrille.com/userfiles/files/soxixufizemilikox.pdfIn PDF document text
    • http://nc-israel.ru/upload/files/89015500324.pdfIn PDF document text
    • https://hanurichurch.org/ckfinder/userfiles/files/sidoremigemovelog.pdfIn PDF document text
    • http://tomaszfilipczak.pl/userfiles/file/4956945168.pdfIn PDF document text
    • https://cowik.pl/upload/48686233359.pdfIn PDF document text
    • https://floridainvestment.cz/files/file/36423290871.pdfIn PDF document text
    • http://aranysolyomfeszke.hu/editor_up/begezap.pdfIn PDF document text
    • http://subventionsbetrug.de/wp-content/plugins/super-forms/uploads/php/files/110mf0cba5tff5359uhb145i5u/digusifepeluzarofotifatid.pdfIn PDF document text
    • https://tssch.in/tssch/application/admin/uploads/file/68000592608.pdfIn PDF document text
    • http://xfswchem.com/upload/files/54066600458.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=how+to+create+apk+file+in+mobilePDF 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_off0000e4fa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4FA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fd0c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD0C 19016 bytes
SHA-256: 20b3198b98c827d1085d598b07e6d78987c6c69a5f12aad3d597dc21ecb5bbae
font_02_sfnt_off00012e5e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12E5E 10784 bytes
SHA-256: 4ad5b3f8d3dcf70214657c5e53391f3ec0412aee568ed575c01caee7dd09678c