Malicious PDF — malware analysis report

Static analysis result for SHA-256 caa1ce4c134a5f83…

MALICIOUS

PDF

99.3 KB Created: 2021-09-21 15:19:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: e7561fe2e0cd0ea814abf608786a786c SHA-1: 6f55aa61620a09228150e826d4612570b02b27eb SHA-256: caa1ce4c134a5f83bd83a91cad2268992846cb63a68fd00da28973f61707cf7f
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to disposable domains and are part of a link farm, indicating a phishing or redirection attempt. ClamAV and ML classifiers also flagged this file as malicious. While no scripts were explicitly extracted, the PDF structure and embedded links suggest an attempt to lure users to external sites, likely for credential harvesting or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9961

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://belv.ru/userfiles/file/30787622508.pdf In PDF document text
    • https://anne-berger.de/sites/anne-berger.de/files/fkcfile/90741827306.pdfIn PDF document text
    • http://www.icf-plant.com/files/file/23345953689.pdfIn PDF document text
    • https://lifesmart.ro/ckfinder/userfiles/files/wegexagudupovufunejewux.pdfIn PDF document text
    • https://bya-ingenieria.com/ckfinder/userfiles/files/48314083791.pdfIn PDF document text
    • https://manage4.realtourvision.com/rtv/ckfinder/userfiles/images/files/mawug.pdfIn PDF document text
    • https://tunguoilon.tunhua.vn/ipp/images/uploads/files/kofenizozeruti.pdfIn PDF document text
    • http://placidlakes.com/larpm/uploads/file/14052181706.pdfIn PDF document text
    • http://emploi.nat.tn/ckeditor/ckfinder/userfiles/files/69177341308.pdfIn PDF document text
    • http://richmediahouse.com/admin/uploads/file/12207286477.pdfIn PDF document text
    • https://sakesushimn.com/userfiles/files/78661444402.pdfIn PDF document text
    • https://orig-shop-gsm.ro/ckfinder/userfiles/files/ganunujesodiwag.pdfIn PDF document text
    • http://vanhacollection.com/images/files/kapiparuzuxujovotunu.pdfIn PDF document text
    • https://sarna-zapiekanki.pl/ckfinder/userfiles/files/sabunujipewenawerepo.pdfIn PDF document text
    • https://retrofitoman.com/ckfinder/userfiles/files/xefemigimi.pdfIn PDF document text
    • http://sinorarechem.com/upload/files/tenosobidov.pdfIn PDF document text
    • https://nhahangphongcanh.com/uploads/files/16957040482.pdfIn PDF document text
    • https://china-glass-mosaic.com/userfiles/files/20210917_220416.pdfIn PDF document text
    • http://kerama.altrodesign.eu/ckfinder/userfiles/files/84214899625.pdfIn PDF document text
    • http://tungalag.mn/userfiles/files/lefijasibijadi.pdfIn PDF document text
    • https://christianboudreau.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613875748bcce---tavupuvizalotakuz.pdfIn PDF document text
    • https://satbietthu.com/luutru/files/28148759514.pdfIn PDF document text
    • https://eqonetech.com/upload/userfiles/files/31741176606.pdfIn PDF document text
    • http://webmba.fr/client/logo/file/kajidesaf.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=square+root+2.5PDF 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_off00011a71.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A71 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00013283.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13283 20772 bytes
SHA-256: 9d8ac9bf8a4298abfa1f19b692d64c1365612e5c9c9c1207396d60527233c757
font_02_sfnt_off0001680e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1680E 10332 bytes
SHA-256: 6a88ef9f5ff6ca855a5465b54c8c587c70ec1801f7f28355e8d8a5b3a921c9cb