Malicious PDF — malware analysis report

Static analysis result for SHA-256 d91b8ef12571c4a4…

MALICIOUS

PDF

82.8 KB Created: 2021-09-08 22:33:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 8a4c236069637530a4ba976e891e2130 SHA-1: 79aa70650ef458c5fbc4eed2d6c891dba47c7145 SHA-256: d91b8ef12571c4a4ea48defb2a61d98b9b7e619c6fe0fb305c8af1256d00c2b5
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by ML classifiers and ClamAV as malicious, with heuristics indicating social engineering tactics. The 'SE_CLICKFIX' heuristic specifically points to instructions designed to bypass macro restrictions by prompting the user to execute commands directly, likely to download and execute a secondary payload. While no scripts were explicitly extracted, the nature of the attack suggests a downloader or dropper functionality.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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
  • ClickFix social engineering attack high SE_CLICKFIX
    Document instructs the user to press Win+R or paste a command into a terminal — consistent with ClickFix attacks that bypass macro restrictions by tricking users into running malicious commands directly
  • 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://www.tri-or.fr/tri-or/ckfinder/userfilesfiles/bavowetewefadonesaxi.pdf In PDF document text
    • http://abwmechanicsville.com/uploads/files/33806755370.pdfIn PDF document text
    • http://amexeuro.com/an3_Uploads/file/lekojalidimadowavibimekuf.pdfIn PDF document text
    • http://musicpark-live.de/userfiles/file/vanigovedikubijad.pdfIn PDF document text
    • http://traktor-tv.de/sites/default/files/file/totoxolixuzur.pdfIn PDF document text
    • https://swagath.co/new/ckfinder/userfiles/files/pinetefejamowina.pdfIn PDF document text
    • http://eternaseguros.net/files/files/laramagisuxivujunoso.pdfIn PDF document text
    • https://lanjutpt1.com/contents/files/70930936586.pdfIn PDF document text
    • https://aawyx.com/sites/default/imageuser/file/48957763418.pdfIn PDF document text
    • https://cuichi177.com/uploads/files/202109060430196087.pdfIn PDF document text
    • https://textosolutionslinguistiques.com/upload/editor/file/gepewaximekamoxo.pdfIn PDF document text
    • http://www.lovebliss.tw/UserFiles/files/jaselopipuvuvemobojoked.pdfIn PDF document text
    • https://sitarasign.ir/data/file/fiduboripiruku.pdfIn PDF document text
    • http://razzledazzleevents.in/userfiles/file/31916050988.pdfIn PDF document text
    • http://zonazero.es/userfiles/file/tevonanebup.pdfIn PDF document text
    • http://techscreening.com/userfiles/files/12269406501.pdfIn PDF document text
    • http://gadkowski.pl/repository/filemanager/file/gaxivisusizonivor.pdfIn PDF document text
    • http://sapthagireesyathra.com/userfiles/file/49291496886.pdfIn PDF document text
    • https://www.vibrationmonitoring.asia/wp-content/plugins/formcraft/file-upload/server/content/files/16137c2af4d0e9---13946124158.pdfIn PDF document text
    • https://ismet.com.br/ckfinder/userfiles/files/47628856999.pdfIn PDF document text
    • https://stpm-sa.com/userfiles/file/33682098901.pdfIn PDF document text
    • http://lumieye.com/userData/ebizro_board/file/sokejenexidozarak.pdfIn PDF document text
    • http://sov.tranovice.org/webpagebuilder/ckfinder/userfiles/files/27100364756.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=things+to+do+on+a+minecraft+serverPDF link annotation
    • 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_off0000dc3b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC3B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f44d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF44D 18836 bytes
SHA-256: 5d1a42985cd9c679f2c8a717588054990f69dc9ffb74242785b3a43ac6e5cee1
font_02_sfnt_off000124f1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x124F1 10908 bytes
SHA-256: b213ad65a1be62309b618d9550d9b614a0e6f80bd4625867b7f9be298d0d6c26