Malicious PDF — malware analysis report

Static analysis result for SHA-256 19e4f017dbb732b8…

MALICIOUS

PDF

84.1 KB Created: 2021-09-12 17:31:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: ed38d494764491ceb0b85b1aae84da43 SHA-1: c5c2fc4d79d2f817b9d1681fb6d0b273731acfed SHA-256: 19e4f017dbb732b8ab14b95d4288b102f43216b216c31ae1b7265f2a524fdbfe
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The sample was detected as malicious by ClamAV and an ML classifier, and exhibits high-severity heuristics related to random and disposable URLs. The PDF contains numerous links to external PDF files hosted on various domains, suggesting a phishing or malware distribution attempt. While no scripts were explicitly extracted, the nature of the links and the PDF structure indicate a likely attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://8foro.exceltur.org/exceltur_nuevo/ckfinder/userfiles/files/jaguso.pdf In PDF document text
    • https://chowdhurytourism.com/ckfinder/userfiles/files/49962043080.pdfIn PDF document text
    • http://finadev-groupe.com/userfiles/file/35034543386.pdfIn PDF document text
    • http://ndc-group.ru/uploads/files/7423728425.pdfIn PDF document text
    • http://thevalleytrader.com/files/rujebedilitelaxexenifo.pdfIn PDF document text
    • http://edu-soft.ru/site/htmlimages/file/91713266246.pdfIn PDF document text
    • http://gojjang.com/uploads/files/88098889714.pdfIn PDF document text
    • http://kstarsmall.net/userfiles/file///rudajawi.pdfIn PDF document text
    • https://www.premiumtrade.ro/ckfinder/userfiles/files/79663316182.pdfIn PDF document text
    • http://classicalgardenfountains.com/uplds/file/81760529027.pdfIn PDF document text
    • https://www.revistadefiesta.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613074a1395e9---jivalinazesifap.pdfIn PDF document text
    • http://taxplus.in/images/contentimages/files/lidojakad.pdfIn PDF document text
    • http://www.halpellet.hu/userfiles/files/buwexo.pdfIn PDF document text
    • http://triumphtoday.org/wp-content/plugins/formcraft/file-upload/server/content/files/1613d50b6b9591---41787377214.pdfIn PDF document text
    • http://arsvet.ru/img/upload/jekibobajaxamise.pdfIn PDF document text
    • http://goldendoodlesofthesierranevadas.com/userfiles/file/fopajavuf.pdfIn PDF document text
    • https://posh.hr/files/24618700765.pdfIn PDF document text
    • http://pietroquatriniarchitetto.eu/userfiles/files/vemirutuzevirajab.pdfIn PDF document text
    • http://drcleancenter.com/uploads/files/202109111131267406.pdfIn PDF document text
    • https://cubic.is/userfiles/file/varivativofa.pdfIn PDF document text
    • http://federicozucchettiarchitetto.eu/userfiles/files/40778725691.pdfIn PDF document text
    • https://bustotoronto.com/userfiles/file/lujidosinazavovekinavid.pdfIn PDF document text
    • http://groupementpecheduloir.com/ckfinder/userfiles/files/diwenijurobagirepofojojoj.pdfIn PDF document text
    • http://goldenpeak.it/userfiles/files/55977655376.pdfIn PDF document text
    • http://bangiyaparishadtoronto.ca/bpt/editor/uploadfiles/86718917606.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=transfer+itunes+playlists+to+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_off0000e3f1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE3F1 17632 bytes
SHA-256: 3866f473caa7a62663875edf40ceb0ad387fa330c81241066c17d08258f99993
font_01_sfnt_off00011190.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11190 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000129a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x129A7 10668 bytes
SHA-256: 38b37d4f561e821e3fa24b55b467ad3857e30bcb441fb08548fdd2c31d155d3e