Malicious PDF — malware analysis report

Static analysis result for SHA-256 a32d781823108782…

MALICIOUS

PDF

74.7 KB Created: 2021-09-26 23:35:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: 107e5d0a8a22d08ad171a1826a367ea9 SHA-1: 2246fcf4438ea3608ece3227162631f56df1ef85 SHA-256: a32d78182310878275afd7fa2cf3a56bf63a42c956766f81331ba260b7009aa1
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many pointing to suspicious domains, and is identified as a link farm designed to redirect users. The `PDF_SEO_DISPOSABLE_LINK_FARM` heuristic indicates a pattern of using disposable hosting for a large number of links, suggesting an attempt to obscure the final malicious destination.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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 http://ngor2-3.com/file_media/file_image/file/gunitadugoji.pdf In PDF document text
    • http://alacarte-husum.de/userfiles/file/pudifufitodame.pdfIn PDF document text
    • https://stpetejazz.com/wp-content/plugins/super-forms/uploads/php/files/uh81ik8j8l7ifekc0upt3ta6r8/kesipugu.pdfIn PDF document text
    • http://studioingegneramato.com/userfiles/files/vorepafezowaxix.pdfIn PDF document text
    • http://www.cda.org.hk/ckfinder/userfiles/files/zesafuxigekojagujaf.pdfIn PDF document text
    • https://strategie-forex.com/ckfinder/userfiles/files/fiwedotorapixidobokej.pdfIn PDF document text
    • http://archetipoingegneria.it/userfiles/files/zedazozun.pdfIn PDF document text
    • http://komputerzagrosze.pl/userfiles/file/44954077593.pdfIn PDF document text
    • http://www.alfapilates.pl/upload/file/vanirubelivetaxulek.pdfIn PDF document text
    • http://bioaec.com/userfiles/files/48128010648.pdfIn PDF document text
    • http://jinwoosmc.com/userfiles/file/menexowudolule.pdfIn PDF document text
    • http://gostium.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614001b44218f---ripefejorosavukukaxa.pdfIn PDF document text
    • https://ptkas.com/kingkong/userfiles/files/1836476121.pdfIn PDF document text
    • http://barefoot.pl/userfiles/file/31561505304.pdfIn PDF document text
    • http://chnli.tw/CKEdit/upload/files/10489763162.pdfIn PDF document text
    • https://huangs.tw/uploads/files/202109040031578177.pdfIn PDF document text
    • https://corpus.bg/files/fck/file/nigiwigazemabumejazimi.pdfIn PDF document text
    • http://highlevel.pl/userfiles/file/67574784546.pdfIn PDF document text
    • http://library.nesdb.go.th/ic/admin/ckfinder/userfiles/files/zupewutusizikanawibewunij.pdfIn PDF document text
    • http://artetendasud.it/userfiles/files/sofovijazojafimeme.pdfIn PDF document text
    • https://www.dogandemir.av.tr/paketler/ckfinder/dosyalar/files/pivexizunaros.pdfIn PDF document text
    • http://aquamedia.cn/ckfinder/userfiles/files/ledivotopabem.pdfIn PDF document text
    • http://konstruktor33.ru/app/webroot/files/files/99281631545.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=coin+master+link+generatorPDF 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_off0000b84c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB84C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d063.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD063 10572 bytes
SHA-256: 0f18faf7f3a3667199c205041783c16144525495eb907ededaaaa1db20e24dd4
font_02_sfnt_off0000e87f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE87F 20192 bytes
SHA-256: 0cd37dbdeb04188177ff951b08130d037fb5a169255789a5c231164b98e82a9c