Malicious PDF — malware analysis report

Static analysis result for SHA-256 16ad4e91cf3aa3eb…

MALICIOUS

PDF

82.2 KB Created: 2021-09-11 12:04:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 580728c2c84340afd4aee54c44481423 SHA-1: 6c05b42135785c36e963a77a9b7191f69e640082 SHA-256: 16ad4e91cf3aa3eb3b845780f0d4c58b21c5533b8fea60ef5b3e62885dd8304e
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected by ClamAV as a phishing trojan and flagged by an ML classifier. It contains numerous embedded URLs, many of which point to suspicious PDF files hosted on various domains, suggesting a link farm or redirection scheme. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, indicating a tactic to distribute or host malicious content across many disposable domains.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9911

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://ajtoablakcentrum.com/_user/file/11144015360.pdf In PDF document text
    • http://socukorglutamatmentesfuszer.hu/ckfinder/userfiles/files/98995292730.pdfIn PDF document text
    • http://miyozenemeryville.com/uploads/files/41665079341.pdfIn PDF document text
    • https://mercerapparelss.com/userfiles/files/lugatevoxer.pdfIn PDF document text
    • https://vvpta-irvine.org/userfiles/file/mabibu.pdfIn PDF document text
    • https://www.barrau-philippe-sedeco.fr/ckfinder/userfiles/files/niwajifikakik.pdfIn PDF document text
    • http://analhospital.net/file/files/zisujefabitewuvaxip.pdfIn PDF document text
    • https://alusol-kw.com/ckfinder/userfiles/files/xejukeroxivamajamis.pdfIn PDF document text
    • http://entryexpress.online/chapter_images/files/42045965251.pdfIn PDF document text
    • https://shreegroupco.com/userfiles/file/xigazegurep.pdfIn PDF document text
    • http://timavoshipsupply.it/userfiles/file/jutijuririwijif.pdfIn PDF document text
    • http://chernogolovka.inhome360.ru/admin/ckfinder/userfiles/files/joziranapo.pdfIn PDF document text
    • https://www.carnesvarejo.com.br/assets/ckfinder/core/connector/php/uploads/files/36407208613.pdfIn PDF document text
    • http://cpk.by/ckfinder/userfiles/files/86257229733.pdfIn PDF document text
    • https://ladymamashop.com/uploads/files/202109040701331193.pdfIn PDF document text
    • http://rw-hse-businessconsulting.de/userfiles/file/lilozisatij.pdfIn PDF document text
    • https://wacee.net/wp-content/plugins/formcraft/file-upload/server/content/files/16137e58a919ba---3086873186.pdfIn PDF document text
    • http://ingpiazza.eu/userfiles/files/fivijegokokoxafazef.pdfIn PDF document text
    • http://cjmfgxfollow.morefriendship.com/upload/files/65218926007.pdfIn PDF document text
    • https://mk-sito.it/uploads/file/jakolomorakapibasi.pdfIn PDF document text
    • https://www.northamericatalk.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613926364c4be---dudojej.pdfIn PDF document text
    • http://trunghungplastic.com/luutru/files/lapig.pdfIn PDF document text
    • http://citranco.com/users/files/lolipoposemusawupa.pdfIn PDF document text
    • http://shuimotongyuan.com/userfiles/file/titebifejanefe.pdfIn PDF document text
    • http://www.musicboxpiano.com/contentfiles/50556091769.pdfIn PDF document text
    • http://dlshixiang.com.cn/ckfinder/userfiles/files/79574626944.pdfIn PDF document text
    • http://neo-net.info/giganet/files/file/94142997914.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=beat+blade+dash+dancePDF 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_off0000dc41.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC41 18164 bytes
SHA-256: 54a894f7a558e41e8917fb2b633c97fb430c88f5d79841970df31af49ff8eae8
font_01_sfnt_off00010b74.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B74 10348 bytes
SHA-256: 0c52abb030e5af740ff65528fc5f2f8815c9714bab85c303c51850b62793f9e9
font_02_sfnt_off000122cb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x122CB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1