Malicious PDF — malware analysis report

Static analysis result for SHA-256 8ca53a5a00a8ce8f…

MALICIOUS

PDF

74.1 KB Created: 2021-09-22 15:51:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 3828aca8f6f229f8a14b98d86a1f09ca SHA-1: 11351a2d4f3ac86faf164c29df96de65db5bc2e8 SHA-256: 8ca53a5a00a8ce8fd946cbd28119b59cac5a3255381e1231ae0da137476a36fa
126 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous embedded URLs, with one heuristic specifically identifying it as a link farm on disposable hosting, suggesting a phishing or redirection scheme. The presence of external URIs further supports this, as they likely lead to malicious content or further stages of an attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://antitumor.org/filespath/files/20210908231721.pdf In PDF document text
    • https://ksuskalology.com/images/file/wemulalixumof.pdfIn PDF document text
    • http://jenan.com/ckfinder/userfiles/files/74352615316.pdfIn PDF document text
    • https://callmarkinvestments.com/callmark/files/52914717774.pdfIn PDF document text
    • http://www.impactit.in/ckfinder/userfiles/files/93393903728.pdfIn PDF document text
    • https://lrsdev.com/userfiles/file/xasofubiwabijinizakisatix.pdfIn PDF document text
    • https://www.spoton.pet/wp-content/plugins/super-forms/uploads/php/files/nbv2j07bjqfdu97op3uuoqn9cd/josaxetiv.pdfIn PDF document text
    • http://parquet-cortes.fr/data/Files/netowofusaba.pdfIn PDF document text
    • http://bridgeonlaw.com/filespath/files/20210920142107.pdfIn PDF document text
    • http://gzlmjx.com/data/home/bxu2343160066/htdocs/uploadfile/files/bajerokovevowanol.pdfIn PDF document text
    • https://zivotzaokny.eu/res/file/75206766466.pdfIn PDF document text
    • http://metabolit.ru/files/file/gofinipol.pdfIn PDF document text
    • https://myphambambi.com/webroot/img/files/17796724237.pdfIn PDF document text
    • https://zmiz.hr/userfiles/file/76096115282.pdfIn PDF document text
    • http://peetersinstallatietechniek.nl/upload/files/77679100828.pdfIn PDF document text
    • https://parc-hotel.info/file/6466138097.pdfIn PDF document text
    • http://twfindia.in/userfiles/files/95967140603.pdfIn PDF document text
    • http://www.consorcio.edu.pe/wp-content/plugins/formcraft/file-upload/server/content/files/1613ab194c6cdf---71884547841.pdfIn PDF document text
    • http://pijntherapie.be/uploads/files/87730174449.pdfIn PDF document text
    • http://happysmilecard.com/uploads/files/xixupekilolusetupizuga.pdfIn PDF document text
    • http://el-master.ru/userfiles/file/79331293877.pdfIn PDF document text
    • https://quangcaowebsitecomvn.xemlaco.com/uploads/files/56226293056.pdfIn PDF document text
    • http://teakdeck.pl/files/file/78969193004.pdfIn PDF document text
    • http://cga82.com/admin/File/vasavubofakurux.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=harry+potter+movies+subtitlesPDF 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_off0000bcca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBCCA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d4dc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD4DC 17568 bytes
SHA-256: 2a5192c916e64c5a88a34c577f0bc759478bbcfe301aa65cd733ba510b90a587
font_02_sfnt_off00010271.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10271 10720 bytes
SHA-256: 2c2201d91e6afa341896608a5d3d53ce61c9a22584b59d0432fecc589e408d6d