Malicious PDF — malware analysis report

Static analysis result for SHA-256 22b22551e022d84a…

MALICIOUS

PDF

80.8 KB Created: 2021-09-11 04:45:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: c47986ffa86aac33e945234d1d6f4190 SHA-1: 448e8c42aabd63c867a4805bff9ffa71ff03db47 SHA-256: 22b22551e022d84ae97fa10c9cc7ed264afc0e30ef7527b912ef42d2e20f62cf
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The file is identified as malicious by ML classifiers and ClamAV, specifically as a phishing trojan. It functions as a link farm, containing numerous URLs pointing to external, potentially malicious sites. The presence of multiple external URIs and the 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic indicate a deliberate attempt to redirect users, likely to phishing pages or to download further malware. The document body is heavily obfuscated and appears to be generated content from wkhtmltopdf, not user-readable text.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9959

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://irlanc.ru/uplcv?utm_term=now+you+see+me+two PDF link annotation
    • http://ziepniekkalns.lv/wp-content/plugins/formcraft/file-upload/server/content/files/16132d4ceba6be---12381082302.pdfIn PDF document text
    • http://lifebeachvilla.com/uploads/image/files/gesukuxuwapakepot.pdfIn PDF document text
    • http://dream-mebel.com/pic/file/27781471972.pdfIn PDF document text
    • http://pusancard.com/userData/board/file/jasipasipagejas.pdfIn PDF document text
    • http://corporatiegids.nl/uploads/files/wirolizesasotofixuniwag.pdfIn PDF document text
    • https://www.paseppe.gr/ckfinder/userfiles/files/xetikubo.pdfIn PDF document text
    • http://mp-journal.com/media/file/kabadozasuduvipozejub.pdfIn PDF document text
    • http://rybarict.cz/webpagebuilder/ckfinder/userfiles/files/pudinoz.pdfIn PDF document text
    • http://truhlarstvisollner.cz/data/file/59372697406.pdfIn PDF document text
    • https://www.rockandroll.blog.br/wp-content/plugins/super-forms/uploads/php/files/mnrlu2231eka3heeeqsskk3u9s/80594244199.pdfIn PDF document text
    • http://profil-metall.de/content/uploads/file/97391560932.pdfIn PDF document text
    • http://biafrapol.pl/pliki/file/virosadote.pdfIn PDF document text
    • http://buyyoutubelikes.com/ci/userfiles/files/50367407957.pdfIn PDF document text
    • https://datenglagi.com/contents/files/xesosuxukoxezinoj.pdfIn PDF document text
    • https://catwalkdogcome.com/editor_upload_image/file/rekewomex.pdfIn PDF document text
    • http://besteva.com/upload/files/juxirifasezo.pdfIn PDF document text
    • http://theofficefurniturestore.com/ckfinder/userfiles/files/39630443876.pdfIn PDF document text
    • http://galenbio.com/images/upload/file/vodelofupubu.pdfIn PDF document text
    • http://tdbakademi.org/userfiles/files/45317750323.pdfIn PDF document text
    • http://thietbiotovn.com/Images_upload/files/62339583339.pdfIn PDF document text
    • http://jinshi66.com/uploadfiles/files/vavefezevubaz.pdfIn PDF document text
    • http://jenistudio.com/upload/FCK/file/tonawanezimujirigafiwivuk.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_off0000d972.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD972 10040 bytes
SHA-256: 0c25ee41ed6f3d43818aec097c0cf5e3c868a53837bd5aedaa9ec2e11641a11b
font_01_sfnt_off0000eff2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFF2 17780 bytes
SHA-256: cb726707b94e860eef68335fc0d2546f9a921a03cf630ad0faa8d55ce67c825f
font_02_sfnt_off00011dcf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DCF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1