Malicious PDF — malware analysis report

Static analysis result for SHA-256 cbdc70c40d06c41e…

MALICIOUS

PDF

82.1 KB Created: 2021-09-17 17:49:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 0d541281bb11f41e575e7e888bc161a0 SHA-1: bc84a0ffd3c91abd85fee1e69a7e18f712a2031b SHA-256: cbdc70c40d06c41ead4aed2d923362924c231c54d52fddae7d072ffe28e41d4a
142 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file flagged by ClamAV as a phishing trojan. It contains embedded JavaScript and numerous links, some of which are part of a link farm on disposable hosting, suggesting an attempt to redirect users to malicious content or downloads. The presence of a visual download button further supports a phishing or social engineering attack vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://thedewakohchang.com/image/upload/File/opukebikanumeloda.pdf In PDF document text
    • http://www.dkmodels.net/ckfinder/userfiles/files/10901158867.pdfIn PDF document text
    • https://mchs.kz/userfiles/File/30974466805.pdfIn PDF document text
    • https://ooobelkom.ru/ckfinder/userfiles/files/dikerodi.pdfIn PDF document text
    • https://konferencii.ru/js/ckfinder/userfiles/files/wovinegipozifabobifin.pdfIn PDF document text
    • http://www.meglobalinc.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1613586fc92bb3---28988115018.pdfIn PDF document text
    • http://siamintertrade.com/file_media/file_image/file/1001813679.pdfIn PDF document text
    • http://everest-c.ru/ckfinder/userfiles/files/dalat.pdfIn PDF document text
    • http://sjmhospital.org/files/js/ckfinder/userfiles/files/bogimape.pdfIn PDF document text
    • https://coastalholidayproperty.com/ckfinder/userfiles/files/48078731922.pdfIn PDF document text
    • https://satnamunicipalcorporation.com/admin/ckfinder/userfiles/files/41210566508.pdfIn PDF document text
    • https://tradingphrases.net/userfiles/files/wikumupugujose.pdfIn PDF document text
    • https://7mark3t2-7aya.com/contents/files/jesatagutebowotuniwebe.pdfIn PDF document text
    • https://avflash.nl/upload/files/gobonidedovukusoso.pdfIn PDF document text
    • http://www.alfainstal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/161356b1ea60db---fumasukimovixewuxezega.pdfIn PDF document text
    • http://sethhukumchandschool.com/userfiles/file/rosijevasojuxopogudege.pdfIn PDF document text
    • http://szentdorottyapatika.hu/files/gonalojurizi.pdfIn PDF document text
    • https://blugarden.eu/file/dusozefexeverugepisegevat.pdfIn PDF document text
    • http://tipsclubcr.com/campannas/file/80579867262.pdfIn PDF document text
    • https://ln80.cn/filespath/files/20210906073810.pdfIn PDF document text
    • http://zhengfutz.com/v15/Upload/file/202191715425336.pdfIn PDF document text
    • https://sensesgrouphk.com/louis/STARKGROUP/ckfinder/userfiles/files/17940930310.pdfIn PDF document text
    • https://xn--z4qq44i.tw/upload/actfiles/7853267932.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BkSY9tpko7c/uplcv?utm_term=device+unlock+app+downloadPDF 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_off0000dcd3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCD3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f4ea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4EA 10488 bytes
SHA-256: eddfcb0c6cfa76aeaf9a878d860d203ab7339b85836c7346d456eeb85c5896f6
font_02_sfnt_off00010ce3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10CE3 17608 bytes
SHA-256: 40e5b83719b54ab9f96b1ed6fa22b42a77928885e0a0aaf06702d4b0c9245c0a