Malicious PDF — malware analysis report

Static analysis result for SHA-256 b97003f86344201d…

MALICIOUS

PDF

69.3 KB Created: 2021-09-28 20:49:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 96321006f9e16b22e1a7b8b94971f4fd SHA-1: 963c6552a67cf9de3e1ef88c03da71b9eb2dcdc9 SHA-256: b97003f86344201dd08b701d68e0febe88f8e941a3aad3242ec176b58e1becbd
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is a PDF identified as malicious by ML classifiers and ClamAV. It functions as a link farm, containing numerous external URIs pointing to various websites. Several of these links are hosted on compromised CMS platforms, suggesting an attempt to distribute malicious content or phish users. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicates a pattern of using disposable hosting for these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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.waetsukai.jp/system/ckfinder/userfiles/files/39986360098.pdf In PDF document text
    • https://nutrishop.in/ci/userfiles/files/42669123470.pdfIn PDF document text
    • https://bizimpin.com/calisma2/files/uploads/6244292465.pdfIn PDF document text
    • https://shellserva.nl/docs/Image/file/tudesebifumomen.pdfIn PDF document text
    • http://ryyw.com/upload/files/2021/09/202109261013561617.pdfIn PDF document text
    • http://assotechne.eu/userfiles/files/metumijexesafumena.pdfIn PDF document text
    • http://gnox.vn/upload/files/duduxubomulozofated.pdfIn PDF document text
    • http://escolacaritas.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614fa5ea2721a---vogasaj.pdfIn PDF document text
    • http://nemochem.cn/upload/files/zosusekutomudozunurolur.pdfIn PDF document text
    • https://bykevin.com/wp-content/plugins/super-forms/uploads/php/files/84c88f25b506ceaff0750c8fb5a5bd5d/danobejokum.pdfIn PDF document text
    • http://osstemcardiotec.com/files/fckeditor/file/1958346712613cdfcc57732.pdfIn PDF document text
    • https://www.allterra.group/wp-content/plugins/super-forms/uploads/php/files/849f6c97c0ac04b531f3c63008937cc2/19394232575.pdfIn PDF document text
    • https://izometal.net/mm/file/78791280694.pdfIn PDF document text
    • https://agribusiness.pk/wp-content/plugins/formcraft/file-upload/server/content/files/1612ebaaf19027---xiwujavin.pdfIn PDF document text
    • http://xn--e1aazeoc7d.xn--p1ai/images/shared/file/xuzazitokozewuwobubuduw.pdfIn PDF document text
    • http://hacoauto.vn/upload/files/jebofajuj.pdfIn PDF document text
    • http://szakkepzosiklos.hu/upload/file/89997143825.pdfIn PDF document text
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/10f9371b8855a826e878f3449c67e30d/48426697350.pdfIn PDF document text
    • http://back2wood.de/userfiles/file/dafojitunef.pdfIn PDF document text
    • https://asken.as/bilder/file/34537155520.pdfIn PDF document text
    • https://tomclarkvoiceovers.com/userfiles/files/9897177450.pdfIn PDF document text
    • http://www.lifestaralberta.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614713e983fd0---31538975413.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=monkey+boxing+hack+mod+apk+downloadPDF 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_off0000ae02.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAE02 11124 bytes
SHA-256: c8a128c549f9836b636b729b689d416cf470aff2b9535201ef2a71ef7964b5e0
font_01_sfnt_off0000c767.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC767 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000df79.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF79 16128 bytes
SHA-256: 6d6522f6c141ee07a120c5aaf12e17650c280d9353550ee9ec580e2f7c515872