Malicious PDF — malware analysis report

Static analysis result for SHA-256 4e450357c21e4ccc…

MALICIOUS

PDF

79.8 KB Created: 2021-09-16 03:51:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 97755e6d943e743d00134241ead4d411 SHA-1: 643822f7b800a851acf7dd80ab49b5cb2aaae027 SHA-256: 4e450357c21e4ccccaf8cd9138074471f90611df4a72ee89d4a39d255cd0c1ea
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The PDF file was flagged by ML classifiers and ClamAV as malicious, exhibiting characteristics of a phishing attack. The 'SE_CLICKFIX' heuristic indicates the document likely instructs the user to execute a command, potentially to bypass security measures and download a secondary payload from one of the numerous embedded URLs. The presence of external URIs and link farm behavior further supports a malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://huntic.ru/uplcv?utm_term=onenote+2016+login PDF link annotation
    • http://eugensa.lt/app/webroot/uploads/userfiles/files/58143782830.pdfIn PDF document text
    • http://iberia-ex.com/images/blog/file/tiwazukutisotedivimesikej.pdfIn PDF document text
    • https://robustbrakes.com/administrator/imagetemp/file/99186009425.pdfIn PDF document text
    • http://karlsbach.de/userfiles/files/16038290538.pdfIn PDF document text
    • http://mayepnuocmia.vn/data/ckfinder/files/90246973871.pdfIn PDF document text
    • http://spbmedax.ru/sites/default/files/uploads/59763033473.pdfIn PDF document text
    • http://www.victorian-manor.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1613da2246d841---19324117413.pdfIn PDF document text
    • https://dolupin.com/calisma2/files/uploads/47498593064.pdfIn PDF document text
    • http://teusz.pl/UserFiles/file/9403559357.pdfIn PDF document text
    • https://profipreklady.cz/www/ckfinder/userfiles/files/34615045858.pdfIn PDF document text
    • https://buonoantonio.it/userfiles/file/6949339136.pdfIn PDF document text
    • http://locnuocvietmy.com/Images_upload/files/xebofudomikegikog.pdfIn PDF document text
    • https://www.aledrukujemy.pl/ckfinder/userfiles/files/situdotosapet.pdfIn PDF document text
    • http://thaymanhinhlaptop.com/userfiles/file/lokadezun.pdfIn PDF document text
    • http://dzirerealtors.com/uploads/4662233321.pdfIn PDF document text
    • https://chokysitohang.com/Uploads/userfiles/files/vabisazavudoradipelad.pdfIn PDF document text
    • https://hardlineconstruct.ro/app/webroot/files/userfiles/files/48092284475.pdfIn PDF document text
    • https://produktybhp.pl/pliki_user/File/gavibulajodidup.pdfIn PDF document text
    • http://hongdacable.com/d/files/53073608323.pdfIn PDF document text
    • https://weblative.com/wp-content/plugins/super-forms/uploads/php/files/i2c4p31j4hid1jojkk9tjdobmc/97805564325.pdfIn PDF document text
    • https://abhrian.com/userfiles/files/falisogetewe.pdfIn PDF document text
    • https://blokhol.com/upload/files/rasilafixojamiro.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_off0000d32a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD32A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000eb41.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB41 10340 bytes
SHA-256: 8699c66ddb55f02b6e785466a8863086fc9c569603259436b1906c8158987820
font_02_sfnt_off000102c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102C6 18112 bytes
SHA-256: f5fbb4a57fe2814e3ee7f5c792a407391bf153ec7c97b1255913e1578b4d3672