Malicious PDF — malware analysis report

Static analysis result for SHA-256 f922753715f40952…

MALICIOUS

PDF

84.7 KB Created: 2021-09-09 19:51:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 4ea3c15a1ec12c87ea5c06d15310161b SHA-1: 3c372fdb1d9b56142a400fc40ee9945c7db6b573 SHA-256: f922753715f40952fad957eb09fb816418aaff7c79bba30acab9cf7bd280b975
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 links, many pointing to PDF files hosted on various domains, suggesting a link farm or redirection mechanism. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a tactic to obscure the true destination by using multiple distinct hosts with single links each. While no scripts were explicitly extracted, the nature of the embedded links and the phishing detection suggest an attempt to trick users into downloading further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://safewatersolutions.in/ckfinder/userfiles/files/9213701104.pdf In PDF document text
    • http://cjmfgx.morefriendship.com/upload/files/18349440933.pdfIn PDF document text
    • http://artechq8.com/beta/uploads/files/65629377904.pdfIn PDF document text
    • https://escolaalfa.com/userfiles/file/10269597303.pdfIn PDF document text
    • https://barcelonacentremedic.cat/files/galeria/files/8303349223.pdfIn PDF document text
    • http://www.tiande-global.com/ckfinder/userfiles/files/sadesiruse.pdfIn PDF document text
    • https://heart-calligraphy.com/uploads/files/202109050127327500.pdfIn PDF document text
    • http://allefrgycg.news-read.com/upload/files/48469331325.pdfIn PDF document text
    • https://rosanaalvarracin.com/userfiles/file/bitetozofin.pdfIn PDF document text
    • https://www.phuketvillarentalandservices.com/ckfinder/userfiles/files/57850912518.pdfIn PDF document text
    • https://hnhaa.com/userfiles/tnejp/files/96259661842.pdfIn PDF document text
    • https://f27szerviz.hu/upload/files/67716383943.pdfIn PDF document text
    • http://alajwakh.com/uploaded_files/userfiles/files/61285729258.pdfIn PDF document text
    • https://www.uflo.edu.ar/ckfinder/archivos/documentos/gasote.pdfIn PDF document text
    • http://siripanyalamphun.com/user_img/files/56578731057.pdfIn PDF document text
    • http://www.psstrecno.sk/wp-content/plugins/formcraft/file-upload/server/content/files/16134ccc70b442---78024819214.pdfIn PDF document text
    • https://pratham.one/file/bukam.pdfIn PDF document text
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/161378d2e8d4b7---xetufodememanenekilimi.pdfIn PDF document text
    • https://4wheelchile.cl/admin/uploads/file/rejuwu.pdfIn PDF document text
    • http://personal.sut.ac.th/chantira/port/ckfinder/userfiles/files/nebogebebetumisiw.pdfIn PDF document text
    • http://slxiang.com/v15/Upload/file/20219817711129.pdfIn PDF document text
    • https://zhongzing.com/uploads/files/202109062036295751.pdfIn PDF document text
    • https://ceccarmaramures.ro/userfiles/file/vobugikidubolib.pdfIn PDF document text
    • https://ajur.rest/uploads/userfiles/file/zizekatezu.pdfIn PDF document text
    • http://genarchi.com/data/temp/file/sobisawegukudubumozu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=download+pokemon+ppsspp+games+for+android+apkPDF 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_off0000e16a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE16A 18992 bytes
SHA-256: 698b96549290e0cb6d9859058482707c7cf41af6ca88fc7ef65b31f13e16477f
font_01_sfnt_off00011383.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11383 10924 bytes
SHA-256: 4664d283d3694d92657ec3cece204fb918d2ee0471a2a70845813f4a4013d35a
font_02_sfnt_off00012c9b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C9B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1