Malicious PDF — malware analysis report

Static analysis result for SHA-256 358e5712ac5f9bf6…

MALICIOUS

PDF

85.7 KB Created: 2021-09-19 03:51:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 353648c2f89354d0751b098c8e46a6c8 SHA-1: a1bc7f90a18b7abf08f0a715e2e26db2bfc254e5 SHA-256: 358e5712ac5f9bf6e955c22b47db1f1f89ab93faf737b29e3ddbd763e88c767e
126 Risk Score

Malware Insights

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

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous embedded URLs, many of which are associated with link farms and disposable hosting, suggesting a phishing or malware distribution scheme. The PDF structure and the presence of external URIs point towards an attempt to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://wastran.ru/uplcv?utm_term=gb+instagram+download+apk+latest+version PDF link annotation
    • http://artwatch.ru/userfiles/file/22388722420.pdfIn PDF document text
    • http://eia-edu.com/userfiles/file/3406205340.pdfIn PDF document text
    • https://fultoys.com/userfiles/givuxibusevim.pdfIn PDF document text
    • http://apsara.ru/userfiles/file/44388162467.pdfIn PDF document text
    • http://dalieuht.com/app/webroot/uploads/files/sizowe.pdfIn PDF document text
    • http://www.kevinbrooks.ca/wp-content/plugins/formcraft/file-upload/server/content/files/161434da6daee8---dukizitusasunukulosusit.pdfIn PDF document text
    • http://marcth.pl/media/fck/file/sotimomego.pdfIn PDF document text
    • https://avflash.nl/upload/files/73957979453.pdfIn PDF document text
    • http://namhungholdings.com/uploads/ckfinder/files/5586200573.pdfIn PDF document text
    • https://trsoftyazilim.com/genelresimler/file/70563138841.pdfIn PDF document text
    • https://apz-arte.com/ckfinder/userfiles/files/norewa.pdfIn PDF document text
    • http://pate4me.com/userfiles/file/87586831688.pdfIn PDF document text
    • http://levne-pohary.cz/UserFiles/File/5338879352.pdfIn PDF document text
    • http://seanbittinger.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/dutegipapasovusafijigakel.pdfIn PDF document text
    • https://lawina-radom.pl/files/file/gazanozozapegikujuzego.pdfIn PDF document text
    • https://taxfirma.com/userfiles/file/mapevoruwani.pdfIn PDF document text
    • http://h-st.nl/bestanden/files/gubogujosetetuze.pdfIn PDF document text
    • http://skkouty.cz/ckfinder/userfiles/files/bapovilagabew.pdfIn PDF document text
    • https://hotnewsmd.deca.md/upload/userfiles/files/rifakumanogebalugufomos.pdfIn PDF document text
    • http://paradisetourkorea.com/FileData/ckfinder/files/20210910_BA5A3DDD39F611D3.pdfIn PDF document text
    • http://luijkzonwering.nl/image/file/latawedirafajeselexas.pdfIn PDF document text
    • http://zhouzhuanx.com/v15/Upload/file/2021918550223396.pdfIn PDF document text
    • http://oryginalnedekoracje.pl/userfiles/file/83485403477.pdfIn PDF document text
    • http://unibeauty.com.br/ckfinder/userfiles/files/72022770131.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_off0000e882.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE882 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010099.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10099 11160 bytes
SHA-256: 9392e1c6cc1c949eaf7fb8b65b0575a67765dbe1bbacc5a1f98e45f03ee585de
font_02_sfnt_off00011a51.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A51 17728 bytes
SHA-256: ea5e3aa957ccbe3558836326bf3cbe0bac597e72530fe6a183ba8d898f42e3f7