Malicious PDF — malware analysis report

Static analysis result for SHA-256 7c8373e144ce2b51…

MALICIOUS

PDF

82.7 KB Created: 2021-09-20 09:54:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 0d2376df500952231b734756ab0d32da SHA-1: 706c631c81c77e07b33271d3022a25eea4fae3e5 SHA-256: 7c8373e144ce2b5199a8c6235f2b48c7163e81b55b4a787542e18194c361ee9a
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.001 PowerShell

The sample is a PDF document flagged as malicious by ML classifiers and ClamAV. It contains numerous external URLs, suggesting a phishing or redirection attempt. Notably, a heuristic indicates a 'Clipboard command execution lure,' where the document instructs the user to copy and paste content into a shell, a common technique to bypass security measures and execute commands. The presence of URLs like 'https://nomylo.ru/uplcv?utm_term=windows+10+pro+full+setup+download' further supports a phishing or malware distribution vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9911

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Clipboard command execution lure high SE_CLIPBOARD_COMMAND_LURE
    Document tells the user to copy or paste clipboard content into Run, PowerShell, cmd, or another shell-like execution context
  • 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=windows+10+pro+full+setup+download PDF link annotation
    • http://quick-thailand.com/images/uploads/file/paputewinukubuguziw.pdfIn PDF document text
    • https://www.webhisto.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1614356a1a361c---87604225249.pdfIn PDF document text
    • http://theemasternetworker.com/ckfinder/userfiles/files/wamezotimifubam.pdfIn PDF document text
    • http://rosniyom.com/userfiles/files/bexutapupoma.pdfIn PDF document text
    • http://centronegozi.com/public/bepilib.pdfIn PDF document text
    • https://consurs.ro/ckfinder/userfiles/files/87955386360.pdfIn PDF document text
    • http://icaalliance.org/filespath/files/20210906082753.pdfIn PDF document text
    • http://cameronhaddock.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f77938f6dd---maxalekodosuzewogafoxit.pdfIn PDF document text
    • https://stollerco.com/testingsites/advantage_aviation/assets/media/file/fujosolizijonufoxijupibip.pdfIn PDF document text
    • http://n-production.com/upload/fckeditor/file/66772562852.pdfIn PDF document text
    • http://gayaarchi.com/userfiles/file/20210917152531.pdfIn PDF document text
    • http://tandartsindex.nl/images/uploads/perotovejewuvebabewipigib.pdfIn PDF document text
    • http://vibrobeton.by/pics/files/29520632791.pdfIn PDF document text
    • http://familie-schiecke.de/images/file/84146442212.pdfIn PDF document text
    • http://stapper.de/sites/default/files/userfilesfile/97988554922.pdfIn PDF document text
    • http://samtle.net/ckupload/files/mijetofopegesul.pdfIn PDF document text
    • https://kiaavcilar.com/upload/ckfinder/files/70993979505.pdfIn PDF document text
    • http://rayocazar.com/images/elfinder-1.1/files/file/72023410053.pdfIn PDF document text
    • https://skinrepublic.vn/webroot/img/files/88803065317.pdfIn PDF document text
    • https://onthespothousing.com/userfiles/file/72159468953.pdfIn PDF document text
    • https://electrodomesticaruano.com/images/ckfinder/files/kigarovuwon.pdfIn PDF document text
    • https://konteshamamotu.com/userfiles/file/tedemilebig.pdfIn PDF document text
    • http://www.cddfct.com/up_files/file/12247140352.pdfIn PDF document text
    • https://fuoriscena.eu/file/tugenuvidexazofibug.pdfIn PDF document text
    • https://igk-lilienthal.de/downloads/11638597116.pdfIn PDF document text
    • https://sibservis.com/ckfinder/userfiles/files/nepusizomamanekibowem.pdfIn PDF document text
    • https://cafesca.info/ckfinder/userfiles/files/jaxovigikaretiluge.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_off0000dcd8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCD8 10844 bytes
SHA-256: d3a07ad151386f8d0bc7c09b7baab831e35a247d333959a3b4bcc4387ac852b1
font_01_sfnt_off0000f612.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF612 17884 bytes
SHA-256: e2e1df4195818c05cca5076b4eafa92f7b5713a71c3c586f6784575fd71219b9
font_02_sfnt_off000124b1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x124B1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1