Malicious PDF — malware analysis report

Static analysis result for SHA-256 b275fa0e02ca0b81…

MALICIOUS

PDF

74.0 KB Created: 2021-10-09 00:02:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-21
MD5: 5a39f1043dfd2bcd0f6b39afb3359168 SHA-1: ad4deda57b15f123e321a9b992f9a912b2c6578e SHA-256: b275fa0e02ca0b813c2fad0d0d3b116308ed9b32a648f2cad5e15e46efc4e6b7
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was identified as malicious by a ML classifier and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, containing numerous embedded URLs that point to potentially compromised websites or disposable hosting. The primary purpose appears to be redirecting users to external, untrusted resources, consistent with phishing or malware distribution tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9971

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://www.prunay-en-yvelines.fr/ckfinder/userfiles/files/vezitajufewo.pdf In PDF document text
    • http://letnipohar.cz/upload/file/kigapuradizi.pdfIn PDF document text
    • https://rubin2000-distribuitorshop.ro/userfiles/file/vujadasuwurawoke.pdfIn PDF document text
    • http://halvani.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613101c0315be---vawaredokejir.pdfIn PDF document text
    • https://selispin.com/calisma2/files/uploads/45422173434.pdfIn PDF document text
    • https://przyklejki.pl/userfiles/xojowulegor.pdfIn PDF document text
    • http://tucholainfo.pl/userfiles/file/59881165230.pdfIn PDF document text
    • https://malimbe.africa/wp-content/plugins/super-forms/uploads/php/files/01e938571871214e66ca3efefda5596e/94498037401.pdfIn PDF document text
    • http://herbwaterthailand.com/userfiles/files/pibegemakiri.pdfIn PDF document text
    • https://daynexweb.com/upload/ckfinder/files/43501435198.pdfIn PDF document text
    • http://studiogiamberardino.it/userfiles/files/kegosajolanafa.pdfIn PDF document text
    • http://parilka.by/var/upload/file/lagewuz.pdfIn PDF document text
    • http://modernplating.com/userfiles/file/pibidujat.pdfIn PDF document text
    • http://ybshajiang.com/userfiles/file/2021-09-13/210913103736689812jtzem4frhei2.pdfIn PDF document text
    • https://protum.se/file/32894981152.pdfIn PDF document text
    • https://sk-developers.com/wp-content/plugins/formcraft/file-upload/server/content/files/16150cc4082b29---vogeriw.pdfIn PDF document text
    • http://www.oschouston.com/osc/wp-content/plugins/formcraft/file-upload/server/content/files/1614cafa60c066---32924359751.pdfIn PDF document text
    • http://jamalcar.com/userfiles/file/tetowenofegefadonageto.pdfIn PDF document text
    • http://duepassidalcentro.it/userfiles/files/mopelinokanubivimugigi.pdfIn PDF document text
    • http://ychnjl.net/userfiles/files/72961088873.pdfIn PDF document text
    • http://dlshixiang.com.cn/ckfinder/userfiles/files/30826427294.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=up+to+par+meaningPDF 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_off0000bc8f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBC8F 10388 bytes
SHA-256: 032c518d5321f70fd7f730bb87e2ced9c16dbd6172a22f87ca53040d2a807a39
font_01_sfnt_off0000d400.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD400 18000 bytes
SHA-256: 30ad6131d535b2afced23d4fe2886d2b08c437d49ae9db5cf220a97c5c15cc36
font_02_sfnt_off0001032f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1032F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1