Malicious PDF — malware analysis report

Static analysis result for SHA-256 826483bf3ec5e849…

MALICIOUS

PDF

71.2 KB Created: 2021-09-25 12:49:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 09ebdda7b94ac901f296a47cb28e7248 SHA-1: 3d11832464a59bc05288df7a556698a24b3ae8b0 SHA-256: 826483bf3ec5e84924aab8dcf1b232e1672f3d4f49de79a8718c88eb32a7731c
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which are on disposable hosting and utilize UTM parameters, indicating a likely phishing or malware distribution campaign. The presence of PDF-specific heuristics like 'PDF_SEO_DISPOSABLE_LINK_FARM' further supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://crysiq.ru/uplcv?utm_term=x+videostudio+video+editor+apk+2020+download PDF link annotation
    • http://shopgraeagle.com/ckeditor/uploads/files/zutovufinofasubela.pdfIn PDF document text
    • http://sunriverps.com/data/editor/file/24976146882.pdfIn PDF document text
    • http://szao-spb.ru/images/news/file/14847644952.pdfIn PDF document text
    • http://jimsclub.net/new/board/img_tinfo/file/20210917105042.pdfIn PDF document text
    • http://antopol.topmebli.com/content/xuploadimages/file/49861465744.pdfIn PDF document text
    • http://eske.hu/wp-content/plugins/formcraft/file-upload/server/content/files/1614cb63e8d68d---66828579640.pdfIn PDF document text
    • http://xn--e1aazeoc7d.xn--p1ai/images/shared/file/19802518297.pdfIn PDF document text
    • https://autoroman-service.ro/imagini_ws/98962592702.pdfIn PDF document text
    • http://sellmysayarah.com/userfiles/files/lubunolegupovebalu.pdfIn PDF document text
    • https://trompis-tondschungel.de/userfiles/file/41980592451.pdfIn PDF document text
    • http://nikolalepojevic5.com/multimedia/file/judojazitefinagexufuni.pdfIn PDF document text
    • https://weishinclinic.com/uploads/files/202109230651135001.pdfIn PDF document text
    • http://www.kigimex.com.vn/ckfinder/userfiles/files/39321567159.pdfIn PDF document text
    • https://cottonweb.net/userfiles/file/33040233563.pdfIn PDF document text
    • https://hanoihome.net/img_duhoc/files/11324465947.pdfIn PDF document text
    • http://brukbet.com/user_images/file/malopojikefoguj.pdfIn PDF document text
    • http://vhktn.at/images/content/files/52343324591.pdfIn PDF document text
    • https://xpress2.eu/ckfinder/userfiles/files/23747679184.pdfIn PDF document text
    • http://ilturismoinitalia.it/userfiles/files/lumoris.pdfIn PDF document text
    • http://losmarinoslanzarote.com/marinarubicon/admin/file/6508611610.pdfIn PDF document text
    • https://driftwoodcc.com/userfiles/files/61331447001.pdfIn PDF document text
    • http://ambulatorioveterinariocamali.com/userfiles/files/javajab.pdfIn PDF document text
    • https://debo-fit.be/userfiles/file///53468868216.pdfIn PDF document text
    • http://cancunday.com/travela/img/files/jadibo.pdfIn PDF document text
    • https://ap-qatar.com/userfiles/files/risuvu.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_off0000b43e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB43E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cc55.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC55 10980 bytes
SHA-256: 987556188fb5d3c59370aa95c2b3dcc53be76fa623c4d88a5a736cac33e09043
font_02_sfnt_off0000e603.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE603 16012 bytes
SHA-256: ae2041985e491f925d5dfa674226db415f645a410c6ebb286da01bb175eb9c75