Malicious PDF — malware analysis report

Static analysis result for SHA-256 f17a08312e8018a5…

MALICIOUS

PDF

74.4 KB Created: 2021-09-16 22:07:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: a6dfd84aaf97b2bdd9c8690c4553f80f SHA-1: 210808255cc567636e86a8b5d9fe39a5f29e73aa SHA-256: f17a08312e8018a5092536b7c6a1bfcb65c52fb424b05c5a950014c5cdb3b1ae
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs, many of which are hosted on disposable domains and appear to be part of a link farm. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The presence of multiple external URIs and the link farm heuristic point towards an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://laborke.ru/uplcv?utm_term=display+pc+screen+on+android PDF link annotation
    • https://consultingexpert.eu/fckeditor/userfiles/file/daxipizojopevapopojufi.pdfIn PDF document text
    • http://acril.ru/ufiles/files/julajet.pdfIn PDF document text
    • https://reha.bg/content/upload/file/narudugo.pdfIn PDF document text
    • http://chamdure.com/DATA/files/tejimesosajiminil.pdfIn PDF document text
    • http://halmar.info/userfiles/file/88299589018.pdfIn PDF document text
    • http://donahoelawfirm.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/devafatoruj.pdfIn PDF document text
    • https://www.ijdsir.com/ckfinder/userfiles/files/71086827279.pdfIn PDF document text
    • https://soechi.com/userfiles/file/pepidotupazunuju.pdfIn PDF document text
    • http://adoriantarla.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16137603fa7fba---10126834476.pdfIn PDF document text
    • http://yishiweb.com/upfiles/files/20210911_170401.pdfIn PDF document text
    • https://iwanbim.iwan.co/userfiles/files/98340353793.pdfIn PDF document text
    • https://esterkins.de/ckfinder/userfiles/files/tudalilofeg.pdfIn PDF document text
    • http://massimobertoarchitetto.com/userfiles/files/bujita.pdfIn PDF document text
    • http://jingmingtai.com/filespath/files/20210916180655.pdfIn PDF document text
    • http://kiajihlava.cz/UserFiles/File/vetibuluja.pdfIn PDF document text
    • https://safetypadlocks.eu/eurostyl/photos/file/94521260647.pdfIn PDF document text
    • http://eaas-journal.org/survey/userfiles/files/19699428119.pdfIn PDF document text
    • https://eklyps.net/images/file/65058173473.pdfIn PDF document text
    • http://gachbinhduong.com/upload/file/misidade.pdfIn PDF document text
    • https://amursvoidom.ru/media/files/lasezifijexekedowezil.pdfIn PDF document text
    • http://www.deep2001.com/images/library/File/gukikelivarade.pdfIn PDF document text
    • http://bezagsecurity.cz/userfiles/81354151942.pdfIn PDF document text
    • http://lmleadmanagement.com/userfiles/files/wogajigasud.pdfIn PDF document text
    • http://transchem-tech.com/Uploadfiles/files/93286086713.pdfIn PDF document text
    • http://infosierra.es/images/editor/68360833939.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_off0000c0ab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC0AB 10524 bytes
SHA-256: 150e514a8c63e928914ebaf5992d2407f73935cef4e8ae11451668b732ad0db1
font_01_sfnt_off0000d8b6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8B6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f0c8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0C8 16740 bytes
SHA-256: 786a284b106ea8fe48d3130171e88e34d92ef6fcd78bb4b62e5d4a7ba21ee9f9