Malicious PDF — malware analysis report

Static analysis result for SHA-256 dbc78f2e5e5c8e7c…

MALICIOUS

PDF

82.5 KB Created: 2021-09-12 16:57:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 7c6184ebc25970848ea0992640770f1f SHA-1: 1737891cdf47514390237a4f6d51e0891832d57d SHA-256: dbc78f2e5e5c8e7c42e6c5060dd7664a41fbfb577ccaf2883aa3f3c7202dd579
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF was flagged by a machine learning classifier and ClamAV as malicious. It contains multiple heuristics indicating it's a link farm pointing to compromised CMS uploads and disposable hosting, suggesting an attempt to obscure the true destination. The embedded URLs, while some are marked benign, are part of a broader pattern of redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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://ellev.fr/upload/files/sukufe.pdf In PDF document text
    • https://parquesanalbertohurtado.cl/ckfinder/userfiles/files/ximutozafemejo.pdfIn PDF document text
    • https://cuisinescartier.ca/upload/editor/file/wizesunalakenobapofa.pdfIn PDF document text
    • https://syteq-pro.com/userfiles/file/3442705777.pdfIn PDF document text
    • https://feng-shuiworld.com/userfiles/file/23502252428.pdfIn PDF document text
    • http://www.instalacionescueto.com/nueva/ckfinder/userfiles/files/84130598666.pdfIn PDF document text
    • http://108shiva.com/userfiles/file/In PDF document text
    • http://www.appsolutely.sg/wp-content/plugins/formcraft/file-upload/server/content/files/1613694cb735c7---lenafutudinapaxiso.pdfIn PDF document text
    • https://mattweidnerlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/161358603ce4ce---sawudofeweposawiwu.pdfIn PDF document text
    • http://lukasikgroup.pl/Image/files/kegixefu.pdfIn PDF document text
    • http://ambulanceservice.pl/userfiles/file/vosiretij.pdfIn PDF document text
    • https://pfollowers.com/ci/userfiles/files/86215801415.pdfIn PDF document text
    • https://taperagi.com/contents/files/remuxifokek.pdfIn PDF document text
    • http://jingkangchem.com/upload/files/67356013994.pdfIn PDF document text
    • http://tsradviseurs.nl/mailing/images/photo/file/2806284052.pdfIn PDF document text
    • https://samavetpharm.com/userfiles/files/rufesaguzup.pdfIn PDF document text
    • http://stin-verdon.fr/assets/Image/files/jezisotipu.pdfIn PDF document text
    • http://drvision.org/wp-content/plugins/formcraft/file-upload/server/content/files/1613afc8f946d7---98024266899.pdfIn PDF document text
    • http://massintech.ru/img/outer/files/momixofisuzujidifegam.pdfIn PDF document text
    • http://cctsw.net/whly/up_files/FCK/file/20210912_134524_125.pdfIn PDF document text
    • http://sarigol.kr/userData/ebizro_board/file/gugutatasosatekamiki.pdfIn PDF document text
    • https://mayphoviet.com/media/ftp/file/xuvuvuposutidop.pdfIn PDF document text
    • https://yantrasearch.com/ckfinder/userfiles/files/89045960547.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=sd+card+is+not+reading+on+my+phonePDF 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_off0000dcf4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCF4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f50b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF50B 11104 bytes
SHA-256: 321e00e9bc1c6f7b9546402eb62d46f05a5fd6833ea87fdcf7c3e7d3efe195b7
font_02_sfnt_off00010e8b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E8B 17736 bytes
SHA-256: c7a58dfb5efcf234fafb219b92ea3468e7ee8b197078be0d3e25901de36b3429