Malicious PDF — malware analysis report

Static analysis result for SHA-256 f5cb0bdd7e40acb4…

MALICIOUS

PDF

71.5 KB Created: 2021-09-25 15:31:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: c7d90e9585ac31340a958f9ddae65b4c SHA-1: 1e20935e875e7023719a0df9d48a56567cf14276 SHA-256: f5cb0bdd7e40acb4ade3fb9a2d899427f55626809b9bc77ed4ee560727dd778e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous links pointing to compromised websites and disposable hosting, suggesting a link farm designed to distribute malicious content. The presence of a URL with 'office 365 apk download for pc' indicates a lure to trick users into downloading a fake application. The ML classifier and ClamAV detection strongly indicate malicious intent.

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 https://synerhu.ru/uplcv?utm_term=office+365+apk+download+for+pc PDF link annotation
    • http://langfordfinancialservices.com/userfiles/files/46144125838.pdfIn PDF document text
    • http://polletnv.be/uploads/files/bidapeta.pdfIn PDF document text
    • http://global-poseg.com/wp-content/plugins/formcraft/file-upload/server/content/files/16142658da3dfc---lagaxiki.pdfIn PDF document text
    • http://fotografoenricogiampieri.it/userfiles/files/133264437.pdfIn PDF document text
    • https://storage-in-motion.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139a5e562873---39983463773.pdfIn PDF document text
    • http://intechsol.kz/wp-content/plugins/formcraft/file-upload/server/content/files/1614e59a83e59d---99212929018.pdfIn PDF document text
    • https://playerpress.com/ckfinder/userfiles/files/famoxijanululamo.pdfIn PDF document text
    • http://cmcthailand.com/ckfinder/userfiles/files/22431810308.pdfIn PDF document text
    • http://fnathservices.com/upload/file/fokomafofofosije.pdfIn PDF document text
    • https://ip-kamera-rendszer.hu/ckfinder/userfiles/files/55819636921.pdfIn PDF document text
    • https://vinacomvietnam.vn/uploads/news_file/tunakonirotozoxozubede.pdfIn PDF document text
    • http://test.uebersetzungen-nesselberger.de/wp-content/plugins/formcraft/file-upload/server/content/files/161457e84f18c5---16543008668.pdfIn PDF document text
    • http://handinks.com/ckfinder/images_store/files/rexomebesix.pdfIn PDF document text
    • http://taihegas.com/filespath/files/20210910232725.pdfIn PDF document text
    • http://eis-pieschel.de/UserFiles/File/tojewokirufesobiveder.pdfIn PDF document text
    • http://sanarina.de/ckfinder/userfiles/files/gajojavepigetinek.pdfIn PDF document text
    • https://milosislandrooms.gr/userfiles/file/98452556025.pdfIn PDF document text
    • http://dh-cell.net/ckfinder/userfiles/files/32786192459.pdfIn PDF document text
    • http://jyotiacademicpress.org/uploads/file/80680467275.pdfIn PDF document text
    • http://nuitsdartistes.eu/images/file/dufananujilujar.pdfIn PDF document text
    • http://op-gold.com/ck_image/files/dazofojodimiga.pdfIn PDF document text
    • http://www.auditsi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16142077d84514---51996637935.pdfIn PDF document text
    • 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_off0000b187.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB187 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c99e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC99E 11024 bytes
SHA-256: 326feadcdc1d5aeeecdbe67930422ac5f6b14ddcd1e1d6e881e16826be8064f6
font_02_sfnt_off0000e373.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE373 17684 bytes
SHA-256: acd6e7455ee0a04a37d5ac830ece69fa8c2add8ebad667f3687b2cb6c21e490f