Malicious PDF — malware analysis report

Static analysis result for SHA-256 a5a93df629bbd8dd…

MALICIOUS

PDF

84.2 KB Created: 2021-09-18 12:25:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-21
MD5: 603dc4f307bc34a75e777d1fcb1a8449 SHA-1: 773483699d59c4042ef72dc04132d1e397392376 SHA-256: a5a93df629bbd8dd36af3bf3af952de6136ecad99057667c79d1a809ea293d30
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous external URIs and is flagged as a link farm on disposable hosting, suggesting it's part of a phishing or malware distribution scheme. Although no scripts were explicitly extracted, the PDF structure and numerous embedded URLs point towards a redirection attack, likely initiated via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://archism.ru/uplcv?utm_term=reducing+data+usage+on+android+phone PDF link annotation
    • http://richmediahouse.com/admin/uploads/file/noponeb.pdfIn PDF document text
    • https://metrosecuritynepal.com/assets/userfiles/files/4171861800.pdfIn PDF document text
    • http://pieseclimaauto.com/files/file/22513539962.pdfIn PDF document text
    • https://matrainagycsalados.hu/userfiles/file/75227087187.pdfIn PDF document text
    • http://rudolphi.nu/userfiles/file/nixelusujuvezekif.pdfIn PDF document text
    • https://grupa-energia.pl/attachments/file/5675863737.pdfIn PDF document text
    • http://shlawllc.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/6568092542.pdfIn PDF document text
    • http://scouttautomotive.com/editor_uploads/system/files/lesuvebob.pdfIn PDF document text
    • https://greenways.at/userfiles/file/62312243662.pdfIn PDF document text
    • https://vinamex.info/uploads/news_file/16893863008.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16145931a50bfd---82384354349.pdfIn PDF document text
    • https://5of7edwardstreet.com/assets/media/files/97587772938.pdfIn PDF document text
    • http://ctkupavna.ru/upload/file/79759093317.pdfIn PDF document text
    • http://www.majbrno.cz/uploads/files/62756484685.pdfIn PDF document text
    • https://e-midas.ro/files/file/27197025874.pdfIn PDF document text
    • https://magnanerie-cazilhac.com/userfiles/file/zorejikonobozoto.pdfIn PDF document text
    • https://theptaynam.vn/upload/files/63351537864.pdfIn PDF document text
    • http://itaxabc.com/userfiles/file/20210917061748_627547039.pdfIn PDF document text
    • https://fabriziochessa.it/userfiles/file/960141579.pdfIn PDF document text
    • https://xn-----6kcabagcgfjsxjciriy6alkh6a7aqk.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/05e36f4ef3bb6a84569410fd7e7a3309/jitemujivel.pdfIn PDF document text
    • https://photojet.net/userfiles/file/kefedasifapigogegalev.pdfIn PDF document text
    • http://shethof.ch/cgi-bin/dynamisch/file/sotidiso.pdfIn PDF document text
    • http://liavanhaeringen.nl/userfiles/files/78063889334.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_off0000e0b1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0B1 10892 bytes
SHA-256: c9f136257818448b23e7a1ffbb457e2ce21bc6ba51b40076018c645fb9b70c9b
font_01_sfnt_off0000f9a5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9A5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000111b7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x111B7 19036 bytes
SHA-256: a951eaeacb8ffe9019ce00722438f9c7b58f13b41345edd1a8565b07de6e1af9