Malicious PDF — malware analysis report

Static analysis result for SHA-256 2be53b01d5c6a52c…

MALICIOUS

PDF

84.4 KB Created: 2021-09-10 03:13:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 9b9ce76e14aa1cf9a73bdee01b07caea SHA-1: 3de93e1bc43967819a4e8761f221da2d4104f472 SHA-256: 2be53b01d5c6a52c3f3e9a799cf6846d0e7d9ccdf2c0ec669812c4406eb79b3f
104 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs, many of which point to external PDF files hosted on domains flagged as potentially compromised or disposable. The ML classifier strongly indicated maliciousness, and the presence of a link farm heuristic suggests a non-standard document purpose. The document body is heavily obfuscated and unreadable, providing no direct user-facing lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 6

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://insolite.lu/img/userfiles/files/18345465151.pdf In PDF document text
    • http://ahkkpcm.org/userfiles/pilularewunajinubisegow.pdfIn PDF document text
    • http://pixel-pro.ru/upload/file/27093035558.pdfIn PDF document text
    • http://telegid.tv/userfiles/file/3068036141.pdfIn PDF document text
    • https://kimcert.net/E/file/xovawofi.pdfIn PDF document text
    • http://studiovalecchi.it/userfiles/files/67936963341.pdfIn PDF document text
    • http://ciarajewellery.com/editor_upload/file/nowom.pdfIn PDF document text
    • http://sieuthikhoacaocap.vn/upload/files/luzaxawaz.pdfIn PDF document text
    • http://corising.info/sa_upload/userfiles/file/20210904100759.pdfIn PDF document text
    • https://0900107678.com/upload/file/vadazadexal.pdfIn PDF document text
    • http://daejonggyoyc.com/userfiles/file/20210909130623.pdfIn PDF document text
    • http://windcampus.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613423aabd2f6---nitelawaguzisuxezidel.pdfIn PDF document text
    • https://thietkeweblongan.com/upload/files/zegutesen.pdfIn PDF document text
    • http://mebizstekla.ru/userfiles/file/jilutewok.pdfIn PDF document text
    • http://erfaspot.com/resimler/files/8550413196.pdfIn PDF document text
    • https://www.limratechnologies.net/wp-content/plugins/formcraft/file-upload/server/content/files/161341536ee6d6---midewuxo.pdfIn PDF document text
    • http://ultrabeauty-ff.ru/userfiles/file/ruxituju.pdfIn PDF document text
    • http://www.garriagricola.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137fdf9141fb---12947397718.pdfIn PDF document text
    • http://www.tiande-global.com/ckfinder/userfiles/files/52155037310.pdfIn PDF document text
    • http://pescepiana.eu/userfiles/files/suzezenufaxemujelaxulaf.pdfIn PDF document text
    • https://datenglagi.com/contents/files/24925966794.pdfIn PDF document text
    • http://studioferrato.it/userfiles/files/kirakazunewekisi.pdfIn PDF document text
    • http://karate-talence.com/newsite/userfiles/files/kinanizelaninufovawu.pdfIn PDF document text
    • http://likuidart.com/files/ckeditor/files/73186887833.pdfIn PDF document text
    • http://lishasurgical.in/ckeditor/ckfinder/userfiles/files/jifuluzo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=2016+indian+idol+winnerPDF 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_off0000e69b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE69B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fead.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFEAD 17888 bytes
SHA-256: a5676c740457201065973880ee155434905a1a2718c24986fa613dbcea7569af
font_02_sfnt_off00012c76.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C76 10424 bytes
SHA-256: 0431df025b2bc756f8a4b4a3e39d4ab30cc4130844c9e78f55dba75580adadd9