Malicious PDF — malware analysis report

Static analysis result for SHA-256 937a9d8bbb69f9f0…

MALICIOUS

PDF

77.2 KB Created: 2021-09-20 05:47:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 4fe71c0ef4b81440380ae5a59c68052b SHA-1: 95e582a24949e779a8e7b1adde14c7a0f59e4ea9 SHA-256: 937a9d8bbb69f9f0389d21f9196750ee3ab66c777ad9958752e88403531add90
134 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The presence of a 'download button' heuristic and numerous external links, many pointing to PDF files on potentially disposable domains, suggests a phishing or malware distribution attempt. The document body is heavily obfuscated and unreadable, providing no further context.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

Heuristics 6

  • 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.
  • 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://qiuyutv.com/userfiles/files/20210911052239.pdf In PDF document text
    • http://yourhealthyanswer.com/ckfinder/userfiles/files/25824272717.pdfIn PDF document text
    • https://www.zolmedis.lt/ckfinder/userfiles/files/gefon.pdfIn PDF document text
    • https://dmshospital.com/mm_engg/files/vadigadidonupororopas.pdfIn PDF document text
    • http://hongphuc.vn/userfiles/file/siliwam.pdfIn PDF document text
    • http://anindecor.pl/files/file/sukewesofajefopetas.pdfIn PDF document text
    • http://rrarental.org/upload/file/purowodadu.pdfIn PDF document text
    • https://kp-bs.ru/upload/files/rexasuxilezunaf.pdfIn PDF document text
    • http://www.smpnuenen.nl/images/files/sugewimofamoxemakad.pdfIn PDF document text
    • http://thsport.dk/ckfinder/userfiles/files/10720510420.pdfIn PDF document text
    • http://traditionsradio.com/wp-content/plugins/super-forms/uploads/php/files/6aa013101b193d3f862e83330b67f77e/64259611953.pdfIn PDF document text
    • http://klgd.spokoino.ru/i/upload/files/89704611810.pdfIn PDF document text
    • http://mtt-association.fr/upload/file/50161502158.pdfIn PDF document text
    • http://ondrejkocar.cz/img/file/16465091589.pdfIn PDF document text
    • http://mzch.pl/userfiles/file/93977754182.pdfIn PDF document text
    • https://cmfnepal.org/userfiles/files/mudaxowoxiwuw.pdfIn PDF document text
    • http://lerucherdesanges.fr/userfiles/file/budeferisexurip.pdfIn PDF document text
    • http://bowenlawmt.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/tilowafiletemejegeranub.pdfIn PDF document text
    • https://kalatranslation.co.uk/wp-content/plugins/super-forms/uploads/php/files/ivj3mg3jiatfks1pibslccvlql/15035564437.pdfIn PDF document text
    • http://k9careclinic.in/ckeditor/ckfinder/userfiles/files/nulomaluxusitorateven.pdfIn PDF document text
    • https://cottonweb.net/userfiles/file/62549110028.pdfIn PDF document text
    • http://madiran-cruduparadis.fr/ckfinder/userfiles/files/21258987757.pdfIn PDF document text
    • https://kltccompany.com/ckfinder/userfiles/files/kozapixikefus.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=fnaf+help+wanted+android+apkPDF 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_off0000c978.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC978 17668 bytes
SHA-256: 215e0256c2e8ad64535cf6c2fead3e38dc43123c8fd1959208c120f25980224f
font_01_sfnt_off0000f744.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF744 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010f5b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F5B 10580 bytes
SHA-256: 57d7f4347b7b18a6ccc8e4b7d22362a632562cfabdd2b0366599fddec00774d7