Malicious PDF — malware analysis report

Static analysis result for SHA-256 b5613f197fa2b972…

MALICIOUS

PDF

88.4 KB Created: 2021-09-19 10:29:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: d1fbcb5a1a2302dfa7de100b98815095 SHA-1: 22ad276fda75a4b04ef0aa1bd7dc48348a8f917a SHA-256: b5613f197fa2b9728426225fa231beaeee7e4dd7f34baef15a71ef554858ce0b
126 Risk Score

Malware Insights

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

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains numerous external URIs and is identified as a link farm hosted on disposable domains, suggesting it's used for distributing further malicious content or phishing. Although no scripts were explicitly extracted, the PDF structure and external links point towards a common phishing or malware delivery vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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 https://crewmak.ru/uplcv?utm_term=the+walking+dead+movie+streaming PDF link annotation
    • http://language-coach.pl/uploads/files/ralojepulazo.pdfIn PDF document text
    • http://christ-china.com/filespath/files/20210918115158.pdfIn PDF document text
    • https://netlandschool.cl/files/vapegipotudiw.pdfIn PDF document text
    • http://cartopack.be/Images/file/1604457069.pdfIn PDF document text
    • http://srmtteaparty.com/uploads/files/202109131907432465.pdfIn PDF document text
    • http://daoltrading.com/userData/board/file/31885573678.pdfIn PDF document text
    • https://www.mobytec.com.br/mobytec/wp-content/plugins/formcraft/file-upload/server/content/files/161442bf8020db---fipebimiw.pdfIn PDF document text
    • https://bazk.info/public_htmluploads/file/36275896189.pdfIn PDF document text
    • http://a-kamen.com/userfiles/file/wovipofavopanupopudise.pdfIn PDF document text
    • https://www.sesc-am.com.br/Selecao/ckfinder/files/gediruvonudejevulu.pdfIn PDF document text
    • http://www.aceitunasdelguadalhorce.es/ckfinder/userfiles/files/kutukewar.pdfIn PDF document text
    • http://heldermusic.nl/ckfinder/userfiles/files/67438237351.pdfIn PDF document text
    • http://kasaitogo.com/uploads/files/55731848943.pdfIn PDF document text
    • https://morabia.fi/images/file/13083048110.pdfIn PDF document text
    • http://gonvvama.net/filespath/files/20210901091827.pdfIn PDF document text
    • https://calprin.com/ckfinder/userfiles/files/59929715530.pdfIn PDF document text
    • http://neogmbh.de/www/sites/default/files/userfiles/file/39245369425.pdfIn PDF document text
    • https://www.marthatrotts.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16146be9ccfa0c---84600648761.pdfIn PDF document text
    • https://manage4.realtourvision.com/rtv/ckfinder/userfiles/images/files/voziperatifelana.pdfIn PDF document text
    • http://pegasomeeting.medcoast.net/ckfinder/userfiles/files/xilexowejedawebesil.pdfIn PDF document text
    • http://k-yoga.org/file_upload/spaw_upload/file/20210916054512.pdfIn PDF document text
    • http://mayepnuocmia.vn/data/ckfinder/files/59688564426.pdfIn PDF document text
    • https://kawanmto.info/contents/files/pijekiputadabokajidovox.pdfIn PDF document text
    • http://shrlie.com/upload_fck/file/2021-9-1/20210901161905933686.pdfIn PDF document text
    • http://eperon-kochersberg.com/img_db/jovokenon.pdfIn PDF document text
    • 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_off0000f436.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF436 10900 bytes
SHA-256: 6cca11169a51812b1a63fc916c5d61cc29738a503026bbd008a304f461b2508b
font_01_sfnt_off00010d15.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D15 18048 bytes
SHA-256: b0afaf0f8cbd8ed078553be0a4adcd07c2da27fa2865482dd591d41d2555c868
font_02_sfnt_off00013bfa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13BFA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1