Malicious PDF — malware analysis report

Static analysis result for SHA-256 f69b55cea8d6f222…

MALICIOUS

PDF

70.0 KB Created: 2021-09-20 23:23:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: d527102cbd5135388e23ade00d602158 SHA-1: c5cdabf3890bbdad320ea54bf4b68390eea002d8 SHA-256: f69b55cea8d6f222c0e9d24f74408d32c6a858d2fc61efd44a5874f45a717585
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected by ClamAV as Pdf.Phishing.Trojan and flagged by an ML classifier, indicating malicious intent. The presence of embedded JavaScript and a large number of external links, many pointing to compromised or disposable hosting, strongly suggests a phishing or malicious content delivery scheme. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, further obscuring its true purpose.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

Heuristics 7

  • 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.
  • 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 https://queure.ru/uplcv?utm_term=zentangle+art+book+pdf PDF link annotation
    • https://1000families.eu/userfiles/file/gimoxexaguzovefejonegutin.pdfIn PDF document text
    • https://stoneappeal.in/FCKeditor/file/49410733870.pdfIn PDF document text
    • http://bestforfishing.com/wp-content/plugins/super-forms/uploads/php/files/666ed166ddba014c024f9260b226e0c8/24062057339.pdfIn PDF document text
    • http://cardealer-space.com/js/upload/files/suferupanom.pdfIn PDF document text
    • http://kooijobs.in/ckfinder/userfiles/files/46031291981.pdfIn PDF document text
    • http://ngnjl.com/userfiles/files/gekilofuvolidaxejububi.pdfIn PDF document text
    • https://domilot.com/uploader/files/leromamebidusis.pdfIn PDF document text
    • https://j26clean.com/upload/files/52978026783.pdfIn PDF document text
    • http://mhzsolutionz.com/userfiles/file/tewovegan.pdfIn PDF document text
    • https://uroci-kursove.com/userfiles/file/tujunex.pdfIn PDF document text
    • http://gmei.lt/ckfinder/userfiles/files/nikazekid.pdfIn PDF document text
    • https://www.sahabatkeluargahomecare.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141afe9458ca---3927223496.pdfIn PDF document text
    • http://cieplej.pl/imgturysta/file/tipimikifasesudagoseviw.pdfIn PDF document text
    • http://partner-support.net/user_data/userfiles/files/bojewa.pdfIn PDF document text
    • http://xn--or3bi2da319p.com/upload/fckeditor/file/41399752510.pdfIn PDF document text
    • http://dishandspoonproductions.com/ckfinder/userfiles/files/lawerijalenuzajomox.pdfIn PDF document text
    • http://orem.mn/uploads/files/mesunoluwufabas.pdfIn PDF document text
    • http://music-summer-courses.eu/upload/files/talejekumugiwuwufufufuxon.pdfIn PDF document text
    • http://jingluo.net/uploadfiles/files/nuxuwovulutoniwafiginu.pdfIn PDF document text
    • http://irinka.org/ckfinder/userfiles/files/43537409375.pdfIn PDF document text
    • http://usmleworkout.com/files/file/liwinugebem.pdfIn PDF document text
    • http://shinserviceodi.ru/wp-content/plugins/super-forms/uploads/php/files/31a34cad1ae387b8dab30210e45c085f/devuzavagebunuwubenu.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_off0000b289.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB289 10608 bytes
SHA-256: a3018155f45a4a35cd89e45e355378ff77ddfcc353ddd24c03bfe84b39474a3b
font_01_sfnt_off0000ca82.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA82 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e294.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE294 15908 bytes
SHA-256: e609f8f2701bde57b02eafcd3e5b0f447b4a83af986b25ef82bd185fb6d5be3d