Malicious PDF — malware analysis report

Static analysis result for SHA-256 df67fe15ce2235e5…

MALICIOUS

PDF

79.0 KB Created: 2021-09-19 04:56:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: aa48023ef2f34e3dbdaeee91ec7f100b SHA-1: d7a75a44e3425d21b624d7b7199c41055d2b7619 SHA-256: df67fe15ce2235e5a2636495f3bccbb325cf4802aa425f38b36bd630ddd14302
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is identified as malicious by ClamAV and an ML classifier, and exhibits characteristics of a link farm. The presence of embedded JavaScript suggests an attempt to execute malicious code or redirect the user. The document body is heavily obfuscated, but the heuristics indicate a phishing or redirection attempt through a series of external links, some hosted on compromised WordPress sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://zamel2.pl/userfiles/file/48340062936.pdf In PDF document text
    • http://client.diffuse.info/files/sozuradovodonopi.pdfIn PDF document text
    • http://grappin-annat-como.com/userfiles/grappin-annat-como.com/file/berow.pdfIn PDF document text
    • https://avukatwebsitesi.trakyasoft.com/upload/files/56776894069.pdfIn PDF document text
    • http://luchetti.it/userfiles/files/vusobi.pdfIn PDF document text
    • http://www.leads-bd.org/app/webroot/js/ckfinder/userfiles/files/wufifikorubepuwezasuvex.pdfIn PDF document text
    • http://groupementpecheduloir.com/ckfinder/userfiles/files/tazexadanepul.pdfIn PDF document text
    • http://duetsepolno.pl/userfiles/file/94111753693.pdfIn PDF document text
    • https://mayxaydungthienlong.com/uploads/files/files/murugitug.pdfIn PDF document text
    • http://ngocphuocjsc.com/public/default/ckeditor/files/neguvekinefip.pdfIn PDF document text
    • http://www.polni.si/Images/files/47801606927.pdfIn PDF document text
    • http://brcassociati.com/userfiles/files/muzuvufid.pdfIn PDF document text
    • https://study-abroad-travel.com/ckfinder/userfiles/file/94176997478.pdfIn PDF document text
    • https://wodepcb.cn/uploadfiles/files/poraderodijesokesap.pdfIn PDF document text
    • http://caerulumpharma.com/upload/files/36827051224.pdfIn PDF document text
    • http://entone.es/wp-content/plugins/super-forms/uploads/php/files/03372e2fbcdf8d3fe539adf2edd588b6/buwizegirokajutinivob.pdfIn PDF document text
    • http://bbmeti.it/userfiles/files/fosobovafonorutugo.pdfIn PDF document text
    • http://wisdomtours.net/upload/file/xesijegade.pdfIn PDF document text
    • http://olivetheater.com/userData/board/file/buwapowokavo.pdfIn PDF document text
    • https://dolmalatrek.com/userfiles/file/murekopa.pdfIn PDF document text
    • http://lnshiyue.com/userfiles/file/20210903160813_1768615822.pdfIn PDF document text
    • http://paintingservicesonline.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16140919c79846---25927776997.pdfIn PDF document text
    • https://www.rapn.ru/ckfinder/userfiles/files/lotanegu.pdfIn PDF document text
    • http://kondicionery-domodedovo.ru/upload_picture/file/tafutegu.pdfIn PDF document text
    • http://www.absolutecateringla.com/wp-content/plugins/formcraft/file-upload/server/content/files/161356fa15c193---gexomiwavewesagaw.pdfIn PDF document text
    • http://clean-ecology.com/Upload/files/35088813867.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=coral+reef+ecosystem+abiotic+factorsPDF 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_off0000cde2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCDE2 10680 bytes
SHA-256: 8be0c877b407052ef3a06c6bac529c426f228a5cea8ff4ea66a3e65bda37e3ec
font_01_sfnt_off0000e678.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE678 18496 bytes
SHA-256: 58f9412e0b7cbde0596e01f972bd4fde194088b2e4355d40e8c58e18dfb1bd06
font_02_sfnt_off0001168c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1168C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1