Malicious PDF — malware analysis report

Static analysis result for SHA-256 a31fc09a9524151e…

MALICIOUS

PDF

78.3 KB Created: 2021-09-17 19:55:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 95ef795889746985dc2d45d9a39f880f SHA-1: f8e4d4c30407404f9952f7130a451cfb955a419d SHA-256: a31fc09a9524151e56f028dd552b61a40074a8ca709e1e4eeb1e76d2b0ab4304
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs pointing to disposable hosting, indicating a link farm designed to redirect users to malicious sites. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' strongly suggests this phishing or malware distribution intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://smidgel.ru/uplcv?utm_term=how+to+write+post+letter+address PDF link annotation
    • https://damsindia.org/admin/uploads/file/tizopasanuvudeguvepopuk.pdfIn PDF document text
    • http://hiro-seiko.com/upload/files/zusorepigereboxinewo.pdfIn PDF document text
    • https://40parables.com/wp-content/plugins/super-forms/uploads/php/files/96aede257f5abf761328d1fe73d28d90/podazebowigusinefitipez.pdfIn PDF document text
    • https://dulsuc.cl/userfiles/file/24323872253.pdfIn PDF document text
    • https://simplehome.ro/ckfinder/userfiles/files/peririm.pdfIn PDF document text
    • http://www.ks-klinika.ru/ckfinder/userfiles/files/zapogarimezit.pdfIn PDF document text
    • http://avstralianature.ru/ckfinder/userfiles/files/wulabusuku.pdfIn PDF document text
    • https://www.pessin-location.fr/ckfinder/userfiles/files/65401091834.pdfIn PDF document text
    • https://zhongzing.com/uploads/files/202109072047221919.pdfIn PDF document text
    • http://kstarsmall.net/userfiles/file///femasojasivixasopo.pdfIn PDF document text
    • https://itracmediav5.com/ckfinder/userfiles/files/bojodanavaxexoladivule.pdfIn PDF document text
    • http://manegedebuitenwijck.nl/uploads/file/mazatarelumedopazixu.pdfIn PDF document text
    • http://www.sosonomo.com/ckfinder/userfiles/files/73165293405.pdfIn PDF document text
    • http://rideabikenews.com/user_img/files/88623588.pdfIn PDF document text
    • http://pol2-simf.ru/userfiles/file/65515049966.pdfIn PDF document text
    • https://www.sgestrecho.es/wp-content/plugins/formcraft/file-upload/server/content/files/1613d60323ed7d---57785582335.pdfIn PDF document text
    • https://blagoustroystvo24.ru/ckfinder/userfiles/files/sodesipugibenelevuragozu.pdfIn PDF document text
    • https://pfollowers.com/ci/userfiles/files/10652204701.pdfIn PDF document text
    • http://guides2alpes.fr/uploads/file/bexowapujej.pdfIn PDF document text
    • https://ladangmimpi2.com/contents/files/24781132375.pdfIn PDF document text
    • http://hotelamadeustorino.com/userfiles/files/33677552352.pdfIn PDF document text
    • https://webtechnocrats.com/upload/file/93255122499.pdfIn PDF document text
    • http://generaltubi.com/container/ckfiles/files/92627099418.pdfIn PDF document text
    • http://kernenshepler.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/fusikupufegososegixadan.pdfIn PDF document text
    • https://groupunsur1.com/contents/files/kanabogazexuz.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_off0000cf25.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF25 10360 bytes
SHA-256: e74de3bb9ac66c0164d2b3c3205ae9b49a504f6a34415d7cbccf107458ec19b6
font_01_sfnt_off0000e6a8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6A8 17316 bytes
SHA-256: 7d040d54ca311b6d1957309ad2ab21ded688453cd87ba1095b40a4c04e7daba6
font_02_sfnt_off00011358.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11358 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1