Malicious PDF — malware analysis report

Static analysis result for SHA-256 563dab7d0cec860f…

MALICIOUS

PDF

79.6 KB Created: 2021-09-16 16:07:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 7113e80a3e6437f739dffa5b7b66611a SHA-1: 538344dcdfa752a9f5ae4560ee163a0310368bfd SHA-256: 563dab7d0cec860f39d1d44688f18af2bfb598d52226bf7b2846f07e8b70f96c
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file flagged by ClamAV as Pdf.Phishing.Trojan and by an ML classifier as malicious. It contains numerous embedded URLs, many of which point to disposable domains and are structured as link farms, a common tactic for phishing or distributing further malware. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic specifically identifies this behavior. No scripts were extracted, but the presence of external URIs and the link farm structure strongly suggest a malicious intent to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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=android+tv+box+black+screen+on+startup PDF link annotation
    • https://degardo.hollandpazsit.hu/ckfinder/userfiles/files/30759389630.pdfIn PDF document text
    • http://mvsexpo.ru/admin/ckfinder/userfiles/files/wejudajiborufijevenejep.pdfIn PDF document text
    • https://kolkataangikar.org/ckfinder/userfiles/files/jizanuvogojunatagukipudo.pdfIn PDF document text
    • https://inunekocp.jp/mailmagazine/upload/files/91020989889.pdfIn PDF document text
    • http://oskarmak.com/userfiles/file/83597001031.pdfIn PDF document text
    • http://webminmax.com/userfiles/file/zugufakenufexeretuveno.pdfIn PDF document text
    • https://izr.fr/files/loradudiwob.pdfIn PDF document text
    • http://peoplefoster.com/pliki/malix.pdfIn PDF document text
    • http://thinhhoanggia.vn/Images_upload/files/medid.pdfIn PDF document text
    • http://mspchicagolaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/6290024765.pdfIn PDF document text
    • http://tunesistudio.eu/userfiles/files/76045037129.pdfIn PDF document text
    • http://ruizhishengwu.com/uploadfiles/file/160416224108.pdfIn PDF document text
    • http://vuason.vn/upload/files/wufopenijogiwitefifikija.pdfIn PDF document text
    • https://catequesisnavarra.org/guiarte_userfiles/files/dufalasila.pdfIn PDF document text
    • http://allgeology.ru/ckfinder/userfiles/files/73566156964.pdfIn PDF document text
    • http://hidrometa.com/images_upload/files/winodaxim.pdfIn PDF document text
    • http://www.kindytennis.com/wp-content/plugins/formcraft/file-upload/server/content/files/161420096996eb---vozotupotawijomurezo.pdfIn PDF document text
    • http://esteticka-stomatologie.cz/files/content/file/kujilesulebix.pdfIn PDF document text
    • http://klimatyzacjaradom.pl/userfiles/file/99156695821.pdfIn PDF document text
    • http://cambridgekapurthala.com/damana/userfiles/file/97170733593.pdfIn PDF document text
    • http://veterinariomauracotti.it/userfiles/files/54812244936.pdfIn PDF document text
    • https://toolsatool.com/userfiles/files/17250938845.pdfIn PDF document text
    • http://52fotki.ru/ckfinder/userfiles/files/82231164420.pdfIn PDF document text
    • http://nousgarage.com/userfiles/file/tubinenivik.pdfIn PDF document text
    • http://quangcaosmsgiare.com/media/ftp/file/tifefugoxabolujopanasipa.pdfIn 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_off0000d951.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD951 10988 bytes
SHA-256: 08616c9842629914a350883faec16f2a25e5cfee952a265155b733f54bd6202d
font_01_sfnt_off0000f2d4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2D4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010ae6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10AE6 17108 bytes
SHA-256: ab9b66e5f5084acd6a1c0972b130eced9fccb152ff5cbc41cdbbf41c69e56c71