Malicious PDF — malware analysis report

Static analysis result for SHA-256 795b0c186cefb77a…

MALICIOUS

PDF

85.6 KB Created: 2021-09-12 22:49:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 19afe72a4f584c9a061dea804fae61bf SHA-1: 6d329a358ba19867d564be5adc7e21c49a54d2d2 SHA-256: 795b0c186cefb77ac7c12335ee645162dd14767f334934baf7a3053ac2689920
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

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 pointing to suspicious domains, suggesting it functions as a link farm or redirection mechanism. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' specifically indicates a tactic of using disposable hosting for link farms, often associated with phishing or malware distribution. While no scripts were explicitly extracted, the nature of the embedded URLs and the detection results strongly suggest a phishing or malware delivery attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 https://tanthueviet.vn/img_data/files/23232670567.pdf In PDF document text
    • https://www.afoa.org.ar/backend/ckfinder/userfiles/files/7533428081.pdfIn PDF document text
    • http://longruiglass.com/ckfinder/userfiles/files/20210908_035544.pdfIn PDF document text
    • https://publicbridge.pl/userfiles/file/bikuwarekamijapol.pdfIn PDF document text
    • http://pm-property.pl/userfiles/file/48379432851.pdfIn PDF document text
    • http://sov.tranovice.org/webpagebuilder/ckfinder/userfiles/files/bodanolidiv.pdfIn PDF document text
    • https://3eyamaichi.com/upload/ckfinder_temp/files/20210909010240.pdfIn PDF document text
    • http://am-assets.com/aom/magnolia/userfiles/file/repukozinuk.pdfIn PDF document text
    • https://icrs-as.com/userfiles/file/84209941524.pdfIn PDF document text
    • https://datajournonepal.org/files/89064578902.pdfIn PDF document text
    • https://vanvoorst.info/uploaded/file/zimivepopur.pdfIn PDF document text
    • http://vyveva.eu/UserFiles/File/64400941905.pdfIn PDF document text
    • https://limblength-sldf.com/userfiles/file/jilupujufapodemugasod.pdfIn PDF document text
    • http://sov.tranovice.org/webpagebuilder/ckfinder/userfiles/files/77708015634.pdfIn PDF document text
    • https://gitteszoneklinik.dk/ckfinder/userfiles/files/52100606519.pdfIn PDF document text
    • https://matharu.ae/userfiles/file/85076527248.pdfIn PDF document text
    • https://traveletrust.com/basefile/traveletrustcom/files/bipexejobiturixokap.pdfIn PDF document text
    • http://www.bestlifepolicy.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1613abb4765872---17974051379.pdfIn PDF document text
    • http://vervesimuhub.com/userfiles/file/95901204359.pdfIn PDF document text
    • http://uran-berlin.com/userfiles/file/bazorobigapitamunufopisok.pdfIn PDF document text
    • https://www.landalastadservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a4b8a78052---41996563574.pdfIn PDF document text
    • http://gmicropilotes.com/uploads/files/xawapakuv.pdfIn PDF document text
    • http://architects-desk.com/uploadsfile/xefimururatutexapomegem.pdfIn PDF document text
    • http://kosmonautika.ee/ckfinder/userfiles/files/valinoko.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=english+movie+hdPDF 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_off0000eb13.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB13 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010325.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10325 17996 bytes
SHA-256: 057a0aebfdb9e64041dc8706a4c6bccdda8e118e30da08e48a727c15735704a5
font_02_sfnt_off0001321b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1321B 10384 bytes
SHA-256: abc4dcc70e9078fe99592808ec8bdc3542b33c5bd2891dc85845be76fc3470e1