Malicious PDF — malware analysis report

Static analysis result for SHA-256 258296dc9bbaa4a0…

MALICIOUS

PDF

72.2 KB Created: 2021-09-16 03:51:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 914f8eb315b509dd88bb52d813dcbc8a SHA-1: 55f8e19a9a76261aab41eafd984a266f63036f36 SHA-256: 258296dc9bbaa4a085801b12c573a0249dba2ea1420171b40035c4497a7ba7e7
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, and contains numerous external URIs pointing to disposable hosting. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicates a link farm on disposable hosting, suggesting a phishing or malware distribution lure. While no scripts were explicitly extracted, the presence of external links and the nature of the heuristics strongly suggest an intent to redirect users to malicious websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 https://allytemp.ru/uplcv?utm_term=maquinas+electricas+enriquez+harper+pdf PDF link annotation
    • http://newabel.com/ckfinder/userfiles/files/71294464066.pdfIn PDF document text
    • https://raselapp.com/userfiles/file/pogegalotigigi.pdfIn PDF document text
    • http://novaserv.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613461c5ad8f9---75154055717.pdfIn PDF document text
    • http://vertex-decor.com/userfiles/file/xijuzi.pdfIn PDF document text
    • http://matras-devison.ru/upload/file/fubozozub.pdfIn PDF document text
    • http://machinegroup.ru/img/outer/files/23225964253.pdfIn PDF document text
    • http://hagelkonzept.de/userfiles/file/musozenijoxonalarovali.pdfIn PDF document text
    • http://boissee.fr/userfiles/file/65554840922.pdfIn PDF document text
    • http://netinflux.net/userfiles/file/9984546313.pdfIn PDF document text
    • https://es21sys.com/userfiles/file/velokobogulexofilu.pdfIn PDF document text
    • https://stpeterscbs.ca/ckfinder/userfiles/files/jezitijib.pdfIn PDF document text
    • http://hevolta.com/upload/file/jimenaxoz.pdfIn PDF document text
    • http://dpnovelty.com/upload/files/wuzis.pdfIn PDF document text
    • https://kurishupally.org/userfiles/file/worus.pdfIn PDF document text
    • https://eetravel.net/file/sowezuxikewuludopekuwud.pdfIn PDF document text
    • http://noithattamphuong.com/upload/files/xuzaxilufore.pdfIn PDF document text
    • https://huangs.tw/uploads/files/202108312206056827.pdfIn PDF document text
    • http://masan315.net/board/imagefile/file/wisaleloxutixuzemimem.pdfIn PDF document text
    • http://aromata.ru/upload/files/wivatibekitalakurefalodak.pdfIn PDF document text
    • https://casasholidays.com/scgtest/team-explore/uploads/files/50822953574.pdfIn PDF document text
    • http://wawa757.com/uploads/files/44456527237.pdfIn PDF document text
    • http://denki-shonan.com/uploadsfile/16574361588.pdfIn PDF document text
    • https://www.iieng.org/editor/ckfinder/userfiles/files/dodedokigiri.pdfIn PDF document text
    • https://orcasproje.com/userfiles/file/jewikegixejunapoxapabufi.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_off0000b94a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB94A 10896 bytes
SHA-256: 41264167b42f7a78b71417ddbe8d126320d8c88ced70123e38357510be4acf04
font_01_sfnt_off0000d23c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD23C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000ea4e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA4E 16136 bytes
SHA-256: 80286ed0d66d096908452166f34a5d55c9ba5f8d1217964972af3f95b58ef242