Malicious PDF — malware analysis report

Static analysis result for SHA-256 d1f2d71e1d376a3c…

MALICIOUS

PDF

85.3 KB Created: 2021-09-23 13:46:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 4f6a395e962f2a1bb8681d32512649ed SHA-1: 5c5b98f9afee9a854df5dffb690c0359c6b59b6e SHA-256: d1f2d71e1d376a3cdc82bbcfba7369b9ee6186b4d2ba1306861d4943d3c355bc
126 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and by an ML classifier as malicious. It contains numerous embedded URLs pointing to other PDF files hosted on various domains, indicating a link farm designed to distribute malicious content. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' specifically identifies this pattern, suggesting a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 http://vansuloi.com/uploads/userfiles/file/mafaluribezajebinu.pdf In PDF document text
    • http://www.elmundodelapiscina.com/ckfinder/userfiles/files/kifexowewisosiguruw.pdfIn PDF document text
    • http://filipdegreef.be/uploads/files/1390451039.pdfIn PDF document text
    • http://www.oschouston.com/osc/wp-content/plugins/formcraft/file-upload/server/content/files/161398376e10ca---12177114658.pdfIn PDF document text
    • http://lncxjzxxw.com/upload_fck/file/2021-9-13/20210913205025977486.pdfIn PDF document text
    • http://dent-pro.cz/pic/file/belikusewegibenurigujepe.pdfIn PDF document text
    • https://elicopter-de-inchiriat.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16132a79155a8c---kabaxilenev.pdfIn PDF document text
    • http://copy-office.it/userfiles/file/buwiwimera.pdfIn PDF document text
    • http://yushendesign.com/images_fck/file/1631872723.pdfIn PDF document text
    • http://yuc-fac.com/uploadfiles/20210921042019.pdfIn PDF document text
    • http://co-wemart.com/careeruserfiles/file/3297152686.pdfIn PDF document text
    • http://vino-charlie.cz/userfiles/file/35768359833.pdfIn PDF document text
    • http://okwmd.com/upload/fckeditor/file/80952450599.pdfIn PDF document text
    • http://kor-ra.ru/UserFiles/file/tagamirutumojuxeriwodud.pdfIn PDF document text
    • https://artsketch.ru/wp-content/plugins/super-forms/uploads/php/files/0ca6fac85df371535b6c77c48bbb4723/bifeweridojemoze.pdfIn PDF document text
    • https://teamcode.net/upload/files/tenuzisubeguradaxijuj.pdfIn PDF document text
    • https://www.artikel238.nl/emmwebbit/resources/ckfinder/userfiles/files/77838047708.pdfIn PDF document text
    • http://behtarinekhodetbash.com/files/files/63070864690.pdfIn PDF document text
    • http://zabbeleecooking.com/ckfinder/userfiles/files/kesugak.pdfIn PDF document text
    • https://drjou-vc.com/upload/files/rejalogumuwes.pdfIn PDF document text
    • https://mcq-exambd.bdbabymart.com/app/webroot/ckfinder/userfiles/files/suvivotazawigar.pdfIn PDF document text
    • http://pactolous.hu/upload/file/8828708275.pdfIn PDF document text
    • http://innovad-ltd.com/userfiles/file/64336807842.pdfIn PDF document text
    • http://voyagevietnamlaos.com/hinhanh/file/vowutofikoramunajobux.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=introduction+to+health+physics+5th+edition+pdfPDF 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_off0000e721.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE721 17660 bytes
SHA-256: 7e446a20033c7ca81d72f399e4b42f3726854c3dbcaca7a36e267caf656aa278
font_01_sfnt_off0001152e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1152E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012d45.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D45 11016 bytes
SHA-256: f187c8ea7f986a090995c6af2ecdfae1c86a9fee0bba3e001a47341ed4fb6f84