Malicious PDF — malware analysis report

Static analysis result for SHA-256 cd8d6b8f9dd057f5…

MALICIOUS

PDF

82.5 KB Created: 2021-09-22 09:16:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e263a20aea4efe766db2d8fe0bf0876d SHA-1: 05fb0a01218906486d40fbb4824535a5d763a621 SHA-256: cd8d6b8f9dd057f53f247e590b9521e0a04c31fb33d2293e2e8e47ae9fbda121
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, with one specifically pointing to a URL containing 'zombie survival 3d mod apk', suggesting a lure for potentially malicious software. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a high number of distinct hosts and links, reinforcing the idea of a link farm designed for malicious redirection. ClamAV detection as 'Pdf.Phishing.Trojan' further supports the malicious classification.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 5

  • 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.
  • 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://chcial.ru/uplcv?utm_term=zombie+survival+3d+mod+apk
    • http://autoneza.cz/UserFiles/File/23069406994.pdf
    • https://oreopay58.com/ckfinder/userfiles/files/luxozulodesonujub.pdf
    • http://orzo.cz/uploaded/files/39023711749.pdf
    • https://xn--bren-mgenwil-gcbf.ch/sites/default/files/fck-uploads/file/64738756328.pdf
    • http://escaletravel.com/userfiles/files/14201578810.pdf
    • http://sky1981.com/asset/uploads/files/5561769265.pdf
    • http://maivietnamesecotati.com/uploads/files/63513209998.pdf
    • http://goksirlambinowice.pl/img/upload/files/gunetatejovuj.pdf
    • http://ersatzmonitor.de/userfiles/file/jenorafuxazaroga.pdf
    • http://bocghedanang.com/media/ftp/file/sogofiw.pdf
    • https://ohcsi.com/ckfinder/userfiles/files/voniviv.pdf
    • http://cichanski.com/Upload/file/33886863415.pdf
    • https://cultureresortpokhara.com/assets/userfiles/files/bijanekatobojogimoji.pdf
    • http://satyamtracparts.com/userfiles/file/29062071236.pdf
    • http://yuanyoujie.vip/userfiles/file/debewanarilesibozij.pdf
    • http://magnumprint.ru/upload/files/7773937558.pdf
    • https://yuktiedu.com/wp-content/plugins/super-forms/uploads/php/files/9ad855a52a96bc1e92c37e20015f31d2/gimejevikaje.pdf
    • http://teleinwestor.com/userfiles/file/zakij.pdf
    • http://i-tos.com/userData/board/file/jofinovafe.pdf
    • http://medicalproduct.hu/images/files/1525739916.pdf
    • https://faktxeber.com/resimler/files/68843912176.pdf
    • https://bselink.com/userfiles/file/nosukunesofirotasol.pdf
    • http://gld-lining.com/user_img/files/radixoriromu.pdf
    • https://zweefvlieg.net/userfiles/file/12669546682.pdf
    • https://defi128.com/userfiles/files/jurokifomabebufate.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000da1e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xDA1E 16792 bytes
font_01_sfnt_off0000f230.bin
80e583fefe737ece1fd16ef11c8596660ca0125690ec757918d9868e3791b906
pdf-font-stream PDF embedded font (sfnt) at offset 0xF230 18588 bytes
font_02_sfnt_off00012320.bin
2c2bb10e9450db3ec3db581137fa8b5a678164a4015a0f671f2c6de5ebf67445
pdf-font-stream PDF embedded font (sfnt) at offset 0x12320 10884 bytes