Malicious PDF — malware analysis report

Static analysis result for SHA-256 835bd5b30ff0f925…

MALICIOUS

PDF

70.8 KB Created: 2021-10-12 01:25:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 3a8e5964d55767e8ac31225367143874 SHA-1: 612446cf27246100dffc5620474f147f96d55e9b SHA-256: 835bd5b30ff0f925a201292a80a238b4d75ec4bb7bd9290b43d462f616b2b030
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs pointing to external PDF files hosted on various domains, suggesting a link farm or redirection mechanism. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicates a high number of distinct hosts, reinforcing the phishing or malware distribution intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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://aibasavar.edu.bd/app/webroot/ckfinder/userfiles/files/5194667318.pdf In PDF document text
    • http://webursitet.org/Files/file/worusinexumamidelig.pdfIn PDF document text
    • http://samtekelektrik.com/files/6246147833.pdfIn PDF document text
    • http://nandishoverseas.com/UserFiles/File/rotalaxatikudalapavif.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16148224aa9459---jonolunozolixe.pdfIn PDF document text
    • https://riondene.ch/img/uploads/file/tirovagozikejavage.pdfIn PDF document text
    • http://chirineli.com/img/lib/file/85843965518.pdfIn PDF document text
    • http://khonggianmang.com/upload/files/xevuvofomupenopajamuf.pdfIn PDF document text
    • http://garant-fond.ru/ckeditor/ckfinder/userfiles/Images/files/wazodolakiwi.pdfIn PDF document text
    • https://elesud.it/img_pagine/file/91411350051.pdfIn PDF document text
    • http://umffz21.ru/admin/ckfinder/userfiles/files/weselabugotitedanenawosa.pdfIn PDF document text
    • http://phukiendoxe.com/media/ftp/file/mijezagu.pdfIn PDF document text
    • http://villalapinetafavignana.it/userfiles/files/20478387643.pdfIn PDF document text
    • http://skup-laptopow.com/wp-content/plugins/formcraft/file-upload/server/content/files/161409b0204631---27438476547.pdfIn PDF document text
    • https://www.barrau-philippe-sedeco.fr/ckfinder/userfiles/files/81808793528.pdfIn PDF document text
    • https://m3nan973ru5-pa571.com/contents/files/fotabifateg.pdfIn PDF document text
    • http://xn--82ca1bkibi6eufn5bh1b7i3e.com/UserFiles/File/sipukadomonosoforem.pdfIn PDF document text
    • http://ketoanaca.com/uploads/image/files/fikenugabadofawixifit.pdfIn PDF document text
    • http://www.jobsincrete.gr/images/_user_na/file/84829036527.pdfIn PDF document text
    • http://canshu.dlzj.net/upload/files/20210919073717665965.pdfIn PDF document text
    • https://takarasushimn.com/userfiles/files/80072401089.pdfIn PDF document text
    • http://france-ex.com/images/blog/file/baxinidexa.pdfIn PDF document text
    • http://thermocomfort.ca/userfiles/file/xorikur.pdfIn PDF document text
    • http://feedproxy.google.com/~r/Xvkpad/~3/HKUGBsJGI0E/uplcv?utm_term=business+crossword+puzzles+with+answersPDF 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_off0000b59c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB59C 15272 bytes
SHA-256: 895e6862238d4d810123a0c0029f362705a0c04120ee2c8c01992f5a3798eba0
font_01_sfnt_off0000dbfb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBFB 10908 bytes
SHA-256: 601e0da93d4531f4ba5104683912b91eeffdc7f1de68de5b977df5554973eeb8
font_02_sfnt_off0000f54f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF54F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1