Malicious PDF — malware analysis report

Static analysis result for SHA-256 7cfef3849e456e12…

MALICIOUS

PDF

84.3 KB Created: 2021-09-23 06:28:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 1f70b9ba9ec898890d0fadd7ca993dbb SHA-1: 3b174fadde4b1605936dd1ad0a9ee141e11f1f7d SHA-256: 7cfef3849e456e126e1f3f1743964ec1ef481b78a62fc10f2f99932569e38ac1
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics, including a machine learning classifier and ClamAV, indicating malicious intent. The presence of numerous embedded URLs, identified as a link farm, suggests a phishing or malware distribution campaign. Although no scripts were explicitly extracted, the PDF structure and embedded links are indicative of techniques used to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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 https://www.bnbtravels.com/ckfinder/userfiles/files/xugogiratiselagexevifi.pdf In PDF document text
    • http://sten.kr/club/data/userfiles/file/20210910100543.pdfIn PDF document text
    • http://universalthailand.com/images/uploads/ckfinder/files/6741067084.pdfIn PDF document text
    • https://artenika.pl/fck/file/4793923414.pdfIn PDF document text
    • http://abnicum.com/files/file/mirakumejodipugebawil.pdfIn PDF document text
    • https://farmaciasacoor.com/site/upload/file/gogufumaxaxoza.pdfIn PDF document text
    • http://ritadas.in/userfiles/file/6802353814.pdfIn PDF document text
    • http://msdoubrava.cz/foto/images/file/36119465248.pdfIn PDF document text
    • http://www.leesii.com/wp-content/plugins/formcraft/file-upload/server/content/files/161446cb7e6388---26173222010.pdfIn PDF document text
    • https://somogyplusz.hu/files/687240425.pdfIn PDF document text
    • https://wmu24.ru/media/file/dugupemilatusubitogas.pdfIn PDF document text
    • https://aventura-agence.lu/userfiles/files/jamesonolopomuruwujul.pdfIn PDF document text
    • https://keluargamimpi.com/contents/files/58275353597.pdfIn PDF document text
    • http://baiduvpn.com/upload/files/39963349867.pdfIn PDF document text
    • http://kondicionery-ivanteevka.ru/upload_picture/file/xonezaxidesoretux.pdfIn PDF document text
    • https://kamwalibais.com/userfiles/file/madugaboloxulanojazopo.pdfIn PDF document text
    • http://anpo.vn/upload/files/82165189595.pdfIn PDF document text
    • https://xn--fiqa735be48e.com/upload/files/72490504702.pdfIn PDF document text
    • http://studiolegaletrotta.eu/userfiles/files/moraverogejadi.pdfIn PDF document text
    • http://robwalker.net/fckupload/file/xosumarozebes.pdfIn PDF document text
    • http://synhbio.com/upload/files/berebakawewuruw.pdfIn PDF document text
    • http://yuc-fac.com/uploadfiles/20210917081205.pdfIn PDF document text
    • http://www.lentilles-progressives.fr/wp-content/plugins/formcraft/file-upload/server/content/files/161427b725c90a---51526060888.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=hack+wifi+wpa2+psk+windows+7PDF 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_off0000e185.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE185 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f99c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF99C 10576 bytes
SHA-256: 9f3ede92eb057559425a2ba774cc5dce98735289ad8a4b4d248d6fc1c134008f
font_02_sfnt_off00011201.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11201 18940 bytes
SHA-256: 3b4b956e78f4592f661ab4ba94f721c12e25d28482467fd1ed2a422bc00d8396