Malicious PDF — malware analysis report

Static analysis result for SHA-256 828a7e2c5c521891…

MALICIOUS

PDF

82.4 KB Created: 2021-04-03 00:55:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: f9bb449312b3b7e0d98ba8da8882792c SHA-1: 7d5bd2dec7d5610bf1f78aef29fe2d08641f5fff SHA-256: 828a7e2c5c52189176fe44637da68911bac1258434ef93968e3daeab4f1bd0ab
134 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous embedded URLs, many pointing to disposable hosting, suggesting a link farm designed to distribute malware. The presence of a 'download button' heuristic further supports the lure-based attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://ponafet.ru/award?keyword=kvs+ldc+answer+key+2020+pdf
    • http://trenketo.buzz/94101435685qwqxw.pdf
    • http://freedate18.xyz/3275288036g54mv.pdf
    • http://bixaxivajujojar.mypressonline.com/51046597723.pdf
    • https://cdn.sqhk.co/duvapegoleva/xiaJja4/translate_words_in_a_picture.pdf
    • http://changepass.online/ukulele_strumming_patterns_4_4d4fg6.pdf
    • http://xuforaxi.22web.org/rumoposupezeniradoxunudej.pdf
    • http://moitender.org/what_is_the_wide_range_achievement_testem15y.pdf
    • http://vuvuga.xyz/sovomebelonababebaliy986e.pdf
    • http://alkostore.xyz/pijijarelakewujirujulfc0gy.pdf
    • http://geguxejap.22web.org/35875433355.pdf
    • http://mailedflkf.site/chicco_keyfit_infant_car_seat_weight_limitvw5b0.pdf
    • https://cdn.sqhk.co/navimoxa/iiITrgh/rivetewuw.pdf
    • http://jogubewuzamofet.iblogger.org/samilofa.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://www.daltonmaag.com/
    • http://fedorahosted.org/lohit
    • http://siwinigap.epizy.com/easy_learning_german_grammar.pdf
    • http://lewupidofiji.epizy.com/what_is_a_magnetic_exercise_bike.pdf
    • http://jenizigigeno.epizy.com/honda_odyssey_2015_manual.pdf
    • http://zozupajekuledus.myartsonline.com/84212905303.pdf
    • http://bikutuvuxaxixo.epizy.com/61084400651.pdf
    • http://zutaturusix.myartsonline.com/javud.pdf
    • http://liwukoxobumex.rf.gd/how_to_turn_off_presonus_audiobox.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e7c0.bin
ebcb4419ca588b15bf8f600e884475a44a8e8bbbe1238f8cfed4cbba750c7d57
pdf-font-stream PDF embedded font (sfnt) at offset 0xE7C0 5260 bytes
font_01_sfnt_off0000f9be.bin
3c64f38f5e6fcde98d6736c4803205201ea12e97d16486492dbe3558020aba13
pdf-font-stream PDF embedded font (sfnt) at offset 0xF9BE 11416 bytes
font_02_sfnt_off00012097.bin
05d2457133b820fa77aa358e30e9acfbad3f04c46ced9a37296d9311117db176
pdf-font-stream PDF embedded font (sfnt) at offset 0x12097 4324 bytes
font_03_sfnt_off00012e96.bin
9a2f1a75f1e8506f68cb7c73edee09eef143a000b524261b1d9866ffed6bb0ec
pdf-font-stream PDF embedded font (sfnt) at offset 0x12E96 3296 bytes