Malicious PDF — malware analysis report

Static analysis result for SHA-256 4c11acc8f8701250…

MALICIOUS

PDF

82.2 KB Created: 2021-09-18 02:12:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 974d702496e51614108098baf6caedec SHA-1: 3562b8c9639e8c6b70634fc895dfd6e4507b5a54 SHA-256: 4c11acc8f870125087ced0a9aff6fb3ea34bc88ee480dd921f8e86f56b57014d
126 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many pointing to disposable domains, characteristic of a link farm designed to redirect users to potentially harmful sites. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, indicating a strategy to obscure the true destination through a network of redirects.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9911

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://ppfi-online.com/userfiles/file/76686309143.pdf In PDF document text
    • http://irths.com/upload_files/files/85352213628.pdfIn PDF document text
    • http://clinicaveterinariailmarzocco.it/userfiles/files/86085999153.pdfIn PDF document text
    • http://chickendaylacrescenta.com/uploads/files/deboxobosozipuwor.pdfIn PDF document text
    • http://hkbroadwin.com/userfiles/zevederikeliri.pdfIn PDF document text
    • http://pjzhengwang.com/upload/file/20210915_173330_153.pdfIn PDF document text
    • https://martabaktelor.com/contents/files/18233769934.pdfIn PDF document text
    • http://gibisch.info/files/files/zozejinasit.pdfIn PDF document text
    • http://zap-interactive.com/uploads/files/33044381226.pdfIn PDF document text
    • https://arizonapoolcontractor.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613bedf7929be---wijirakedefa.pdfIn PDF document text
    • https://www.lorenzofranzone.it/wp-content/plugins/super-forms/uploads/php/files/2832f20d304b94d98c8d4266b2f582a5/16763390935.pdfIn PDF document text
    • https://classoft.ro/userfiles/file/33759279158.pdfIn PDF document text
    • http://www.vinoplaza.nl/img/upload/files/29131804118.pdfIn PDF document text
    • http://study4student.com/cache/fck_files/file/dotaw.pdfIn PDF document text
    • http://livilgirls.com/files/gizaj.pdfIn PDF document text
    • http://ingpiazza.eu/userfiles/files/80946613291.pdfIn PDF document text
    • http://reyazahmad.bscsaoner.in/ckfinder/userfiles/files/98233424920.pdfIn PDF document text
    • https://coastalholidayproperty.com/ckfinder/userfiles/files/82748229107.pdfIn PDF document text
    • https://sreekanakananda.com/ckfinder/userfiles/files/rekebivazuzo.pdfIn PDF document text
    • http://digivideos.net/ckfinder/userfiles/files/7750628907.pdfIn PDF document text
    • http://gpp300.fr/userfiles/file/natamolikefuvalukirasesi.pdfIn PDF document text
    • http://metapolar.hu/tmp/51552706239.pdfIn PDF document text
    • https://vleek.com/uploads/files/ponumaxolawedewatez.pdfIn PDF document text
    • https://forumsevens.com/images/file/74395891807.pdfIn PDF document text
    • http://studiolorenzino.eu/userfiles/files/16156842872.pdfIn PDF document text
    • https://v-rshine.com/upload/images/files/7537352766.pdfIn PDF document text
    • http://www.c-l-r-p.com/admin/ckfinder/userfiles/files/vadatefuxaw.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=call+it+sleep+pdfPDF 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_off0000dff1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFF1 10200 bytes
SHA-256: d80b2e57351d557e0eb39886a76a20f41b2ea4667ba0b8ac633c51beded18136
font_01_sfnt_off0000f6e9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6E9 17016 bytes
SHA-256: 136e930bb7bbdcb44324aee216a36f018c28c956119a6638e5da64cfda2ef493
font_02_sfnt_off0001230f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1230F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1