Malicious PDF — malware analysis report

Static analysis result for SHA-256 4f923c7f7edcf461…

MALICIOUS

PDF

84.0 KB Created: 2021-09-15 16:15:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 09dd3787d282be43225035528e35b9a8 SHA-1: 6559ba021f54e6917bad4a559d9c92dd00272b0d SHA-256: 4f923c7f7edcf4613c9be95442fecdd54417ec11ce7ee6cc48079191a00109c7
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous embedded URLs pointing to external sites, many of which are structured as link farms for software downloads, suggesting a phishing or malware distribution lure. The presence of external URIs and the overall structure align with techniques used to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://nomylo.ru/uplcv?utm_term=efootball+pes+2020+app+download PDF link annotation
    • https://funcarele.com/ckfinder/userfiles/files/sejudera.pdfIn PDF document text
    • https://esterkins.de/ckfinder/userfiles/files/57063285829.pdfIn PDF document text
    • https://thietbidiensino.vn/media/ftp/file/20650453608.pdfIn PDF document text
    • http://musthighschool.mn/ckfinder/userfiles/files/1547553071.pdfIn PDF document text
    • https://tlproduct.com/userfiles/file/mugiwovufadazexofitife.pdfIn PDF document text
    • http://polins.org/public/userfiles/file/xamefobaxiwerez.pdfIn PDF document text
    • http://mariondhuique-mayer.com/data/file/28763512082.pdfIn PDF document text
    • http://sooclose.eu/upload/File/vupexa.pdfIn PDF document text
    • https://svltv.in/userfiles/files/74959644159.pdfIn PDF document text
    • http://szentimresiklos.hu/upload/file/lixijibotaduvelerakex.pdfIn PDF document text
    • https://onhimalayas.com/ckfinder/userfiles/files/18697583045.pdfIn PDF document text
    • http://nexxosrealty.com/userfiles/files/7923708985.pdfIn PDF document text
    • http://hfnhsw.com/upload/files/lajixusaxawokexu.pdfIn PDF document text
    • http://dienvietbac.com/uploads/files/rezoxajixuzesabidurab.pdfIn PDF document text
    • https://atkarisuli.hu/userfiles/file/zemolalalotibebip.pdfIn PDF document text
    • http://ktcz.eu/files/files/kevatusitafizufatetufisu.pdfIn PDF document text
    • https://cape-electronics.com/media/file/bidonawototudipo.pdfIn PDF document text
    • http://divyabodhanam.org/userfiles/file/82295854726.pdfIn PDF document text
    • http://recruiters-zone.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f43133b8b4---nojilivoxoredixutiro.pdfIn PDF document text
    • http://www.icareonline.net.au/ckfinder/icare/files/ridunupewezebogew.pdfIn PDF document text
    • http://daming-school.com/userfiles/file/kogabawojazekixigimetuxe.pdfIn PDF document text
    • https://discovery99.com/userfiles/file/relupakezepubonegibaz.pdfIn PDF document text
    • http://ozkayalarlojistik.com/userfiles/file/15094635596.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_off0000e1b3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1B3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f9c5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9C5 18464 bytes
SHA-256: 72068e79513205bbcc141cde5a474e9515711bf2d592008a5a04a5470c6ab971
font_02_sfnt_off000129ea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x129EA 10748 bytes
SHA-256: 6bbe28f4aec7b6b83854e7a8b564a6d88d54f71eadabb1e2c2a4a28b244dfbcb