Malicious PDF — malware analysis report

Static analysis result for SHA-256 12c376ad139c53da…

MALICIOUS

PDF

83.6 KB Created: 2021-07-21 13:46:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: b219d9955e15921fef6cc48c1f26e850 SHA-1: e04a7995e20e04b653a74bbc99453d9c7ce6edfd SHA-256: 12c376ad139c53daf4f12bb7d425de48211e682a45184e75e50ce882ab033f2b
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript, which is a common technique for initiating malicious actions. Heuristics indicate the PDF acts as a link farm, directing users to compromised WordPress sites and disposable hosting, likely to download further malicious content. ClamAV and ML classifiers strongly indicate malicious intent, with the embedded JavaScript likely responsible for fetching and executing a second-stage payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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.driftime.ee/wp-content/plugins/formcraft/file-upload/server/content/files/1607efecebaa22---25424125709.pdf In PDF document text
    • https://armagedonspedycja.pl/files/file/89438537271.pdfIn PDF document text
    • https://brylka-kfz.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608e2f13dba51---90535100789.pdfIn PDF document text
    • https://londonvipchauffeur.co.uk/wp-content/plugins/super-forms/uploads/php/files/5a1a7bd652c6b8169bc5fe5e07d1b2cc/92493306040.pdfIn PDF document text
    • https://buddingheights.org/wp-content/plugins/formcraft/file-upload/server/content/files/16073f5ece4d7f---vuguzixilurepotaduraj.pdfIn PDF document text
    • http://kyanite.tv/userfiles/file/pitatipojunifofijijija.pdfIn PDF document text
    • https://chinatupai.com/web/js/ckfinder/userfiles/files/xofekorowiguwu.pdfIn PDF document text
    • http://botosani.ro/img/uploads/file/rexubetetinedepatuvu.pdfIn PDF document text
    • http://emailreceptionist.net/userfiles/file/vipek.pdfIn PDF document text
    • https://hsse.cl/files/39448488313.pdfIn PDF document text
    • http://goldcoil.com/uploadfiles/files/4793588163.pdfIn PDF document text
    • http://www.moteco.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160989aad7d72b---teferogabuk.pdfIn PDF document text
    • https://ssvacancy.com/ckfinder/userfiles/files/18563549197.pdfIn PDF document text
    • http://nandeestationery.com/userfiles/files/42341194685.pdfIn PDF document text
    • http://compie.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1609660d8aead5---zetup.pdfIn PDF document text
    • http://12shio5.com/contents//files/6023258102.pdfIn PDF document text
    • http://furkansigorta.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1606d0afb0166d---19280349004.pdfIn PDF document text
    • http://syuncyoku.jp/upload/file/zafezufotana.pdfIn PDF document text
    • https://vleek.com/uploads/files/zumun.pdfIn PDF document text
    • https://istanajpdua.com/contents//files/renejufizikapovazasev.pdfIn PDF document text
    • https://faceless.me/userfiles/files/vusewelowatiputemepafonif.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=wrightsville+correctional+facilityPDF 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_off0000e507.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE507 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fd1e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD1E 10788 bytes
SHA-256: 7899cc73c0a5b3166e2ff5a76b3e18795893fe7a07a9a1835c0690dd248d8c0e
font_02_sfnt_off000115f3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x115F3 16700 bytes
SHA-256: 3a511e4fb285ebdc1f692c41f21fb223b080b7c17458180d14b6badf5deed235