Malicious PDF — malware analysis report

Static analysis result for SHA-256 d4778c0ace20c0ee…

MALICIOUS

PDF

69.4 KB Created: 2021-09-25 01:03:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: ffe3281e6f5640c0331ecfa71257aea2 SHA-1: fe70ba949a7012a2246b4e2a2ca30105b67a8882 SHA-256: d4778c0ace20c0eef576c344815b965001e76488a8196bca8530b3fa702ae1f6
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains numerous embedded URLs, many of which point to external PDF files, suggesting a link farm or redirection mechanism. While no scripts were explicitly extracted, the PDF structure and embedded URIs are indicative of techniques used for phishing or distributing further malware. The presence of external URIs and the 'link farm' heuristic strongly suggest an attempt to direct the user to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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.smartusb.info/images/library/File/67136660166.pdf In PDF document text
    • http://seyrimerdin.com/userfiles/file/5626725615.pdfIn PDF document text
    • https://mkycc4.com/kycc4.com/userfiles/files/kiwebujedop.pdfIn PDF document text
    • http://xn----7sbbbizu2bxaod.xn--p1ai/userfiles/file/wujoruwewisemexez.pdfIn PDF document text
    • http://stomerijindex.nl/images/uploads/75458687256.pdfIn PDF document text
    • http://www.mediagrand.hu/data/editorfile/pavozunupaxekosapadaxez.pdfIn PDF document text
    • http://www.roosprommenschenckelfoundation.nl/ckfinder/files/files/99759464269.pdfIn PDF document text
    • http://pocatellocampfire.com/wp-content/plugins/super-forms/uploads/php/files/kgvjauq3hn04lb6qkfu7hklkep/kuxeretaporasolikesu.pdfIn PDF document text
    • https://iagclaims.endataclaims.com/ModCoreFilesUploaded/file/79424929069.pdfIn PDF document text
    • https://dolnoslaskialarmsmogowy.pl/imgturysta/files/baxilajuvefuxipab.pdfIn PDF document text
    • https://prestinieurope.ch/userfiles/files/femol.pdfIn PDF document text
    • https://bgg.pirkitpadangas.lt/ckfinder/userfiles/files/27589883544.pdfIn PDF document text
    • https://reha.bg/content/upload/file/18100956496.pdfIn PDF document text
    • http://domario.ru/userfiles/file/47822036680.pdfIn PDF document text
    • http://megat.pl/uploaded/fck_files/file/lufubekunuwon.pdfIn PDF document text
    • http://supragyn.cz/userfiles/file/ruxal.pdfIn PDF document text
    • http://www.hebrewforreadingcomprehension.com/content/93300903478.pdfIn PDF document text
    • http://runbo.net/upfiles/files/16306484798665.pdfIn PDF document text
    • https://shiprapublication.com/uniformkontakt/userfiles/image/files/76739097531.pdfIn PDF document text
    • https://nazragame.com/calisma2/files/uploads/mifiwupanituw.pdfIn PDF document text
    • http://kfoodntea.com/dataroom/file/90380118704.pdfIn PDF document text
    • https://homestayhoian.vn/uploads/image/files/44745580588.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=back+scratch+testPDF 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_off0000b04d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB04D 16244 bytes
SHA-256: c54926d48983813fe7c6a06b3abd9cd8e94ba8fb020b93c8c497f5df77757df7
font_01_sfnt_off0000d944.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD944 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f15b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF15B 10108 bytes
SHA-256: cdb66b8b2395adc3827a9ee4d577e28f84c08680b57b1d05b224704a302e2de3