Malicious PDF — malware analysis report

Static analysis result for SHA-256 a8591635e5beee8f…

MALICIOUS

PDF

81.0 KB Created: 2021-09-11 09:52:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 665d1561ec420db419acae824b2ee8d7 SHA-1: 58d6d6a1f9f13f1d6e3cd9d0c62ba38b380dbbc1 SHA-256: a8591635e5beee8f22f767e075cc163245205ba3e10edb6a0225717919fde2ad
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The PDF contains numerous embedded URLs, many of which point to suspicious domains and appear to be part of a link farm, suggesting a phishing or malware distribution scheme. While no scripts were explicitly extracted, the PDF structure and embedded URIs are indicative of an attempt to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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://basar-hemeringen.de/ablage/userfiles/files/gezaledoredojavifomov.pdf In PDF document text
    • http://breakevenpoint.pl/uploads/editor/file/30655860927.pdfIn PDF document text
    • https://408of53crownstreet.com/assets/media/files/lujukiwakujijav.pdfIn PDF document text
    • https://konzolstudio.ro/uploaded_files/file/86311268564.pdfIn PDF document text
    • http://aallergy.friend-match.com/upload/files/mizusudozugigezofabug.pdfIn PDF document text
    • http://kayapalinakliyat.com/file/punax.pdfIn PDF document text
    • http://elvirajogsi.hu/ckfinder/userfiles/files/23509199075.pdfIn PDF document text
    • http://bulgankhangai.mn/userfiles/files/7733431106.pdfIn PDF document text
    • http://stroisvias.ru/userfiles/file/pajejojexoguwuk.pdfIn PDF document text
    • http://sahcarpets.com/userfiles/file/442081493.pdfIn PDF document text
    • https://gpagroup.in/wp-content/plugins/formcraft/file-upload/server/content/files/1613284543dc1e---bipoz.pdfIn PDF document text
    • http://yuli-china.ru/d/files/82168827229.pdfIn PDF document text
    • http://tjsyjdq.com/v15/Upload/file/202194147587907.pdfIn PDF document text
    • http://qdxqw.com/uploadfile/file/4730437746.pdfIn PDF document text
    • http://thewesternmist.com/userfiles/file/gexegamipizuwilinibumito.pdfIn PDF document text
    • http://toyotaquangninh.org/data/dulieu/files/megijuxoporogapodetidul.pdfIn PDF document text
    • http://gaziogluenerji.com/images_upload/files/55473520086.pdfIn PDF document text
    • http://marinapogon.pl/upload/file/kagesebokadokemuzefurupar.pdfIn PDF document text
    • http://knupress.com/pds/editor/file/zulibijabezudawoturon.pdfIn PDF document text
    • https://claphamjunction.com.au/wp-content/plugins/super-forms/uploads/php/files/030856e1942576360dce6a37c4bdbdfa/83595045330.pdfIn PDF document text
    • https://beysukonaklari.com/ckfinder/userfiles/files/badunalemofijejafuv.pdfIn PDF document text
    • https://10s317.com/uploads/files/202108311809028299.pdfIn PDF document text
    • https://thietbivesinhanhhuy.com/asset/files/74621752496.pdfIn PDF document text
    • http://tsg-vaganovskoe.ru/ckfinder/userfiles/files/60469361394.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=comment+installer+un+jeux+sur+androidPDF 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_off0000d48b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD48B 10772 bytes
SHA-256: 1d378f45d91fdc96bfb3c4bdfacec3036d1c0c7c8beed26b9d5aeb59718e9cf7
font_01_sfnt_off0000ed52.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED52 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010564.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10564 19580 bytes
SHA-256: bf82a2dad484b92fcf81b5a806ae4314db1974c50cbd57910716b8ec17c763b4