Malicious PDF — malware analysis report

Static analysis result for SHA-256 731fcbf8e08bafba…

MALICIOUS

PDF

74.2 KB Created: 2021-09-22 14:03:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-29
MD5: 43548f06e4e19545bef4faff8a541424 SHA-1: e4b5b8a515e53ecf01e1c7140e61c50ef9794435 SHA-256: 731fcbf8e08bafbac9d168ff62852d4618e65051e6cf533429a90cb3776480f4
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as a phishing/malicious PDF by ClamAV and ML classifiers. It contains numerous external URIs and is identified as a link farm on disposable hosting, suggesting an attempt to redirect users to malicious sites. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicates a high volume of links to different domains, typical of phishing or malware distribution campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://medvor.ru/uplcv?utm_term=crows+zero+yify PDF link annotation
    • https://wita.lt/images/files/14926065170.pdfIn PDF document text
    • https://svetplus.com/userfiles/files/pevoxujofuweribefunopex.pdfIn PDF document text
    • http://www.fishandcosolicitors.com/uploads/files/puwovefofogisujoxubumu.pdfIn PDF document text
    • http://kredoteka.ru/uploads/file/89309966239.pdfIn PDF document text
    • http://studiodispirito.it/userfiles/file/44844164731.pdfIn PDF document text
    • https://securitydm.net/slicice/file/35066648868.pdfIn PDF document text
    • http://www.hkqi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e196d4bf4d---viladenoz.pdfIn PDF document text
    • https://ferado.vn/userfiles/file/41405522513.pdfIn PDF document text
    • http://tecresconsolidamentorestauro.it/fck_data/file/zukores.pdfIn PDF document text
    • http://hoilhpnqbthanh.com/upload/file/96791120617.pdfIn PDF document text
    • http://dungcumaymoc.com/Images_upload/files/wegupinarizomebin.pdfIn PDF document text
    • http://prunay-en-yvelines.fr/ckfinder/userfiles/files/74264013591.pdfIn PDF document text
    • http://cec-intl.ru/app/webroot/files/file/46800914507.pdfIn PDF document text
    • http://sdes.in/uploads/49527930533.pdfIn PDF document text
    • https://auf.vn/wp-content/plugins/super-forms/uploads/php/files/msk0rui0h9som5okl3ah743617/25672960728.pdfIn PDF document text
    • http://fmmvn.net/userfiles/files/muzojirogivudililuposof.pdfIn PDF document text
    • http://phuquytravel.com/nguyenvanlinh/files/dagirugezonadebuz.pdfIn PDF document text
    • http://rooptex.com/uploads/vobijerube.pdfIn PDF document text
    • http://avstralianature.ru/ckfinder/userfiles/files/famufar.pdfIn PDF document text
    • https://ezsprinting.com/userfiles/file/68733089937.pdfIn PDF document text
    • https://alternativecarrepair.nl/userfiles/file/49006112575.pdfIn PDF document text
    • https://dolmalatrek.com/userfiles/file/74832656416.pdfIn PDF document text
    • http://livelyway.com/ckfinder/userfiles/files/bavusaloba.pdfIn PDF document text
    • http://adice-area.com/pictures/files/88261314899.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_off0000c030.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC030 16748 bytes
SHA-256: 1ab2fa6d0b0a9731547ce28e7bfdfa254f312eeda257ea6b5cf7baaf1d680350
font_01_sfnt_off0000ec10.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC10 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010427.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10427 10088 bytes
SHA-256: cc9fef647f84a0a0018eaef091016c75d5b68677d7798707605d54ac7e0e25d9