Malicious PDF — malware analysis report

Static analysis result for SHA-256 df89d2793f5921c9…

MALICIOUS

PDF

94.7 KB Created: 2021-10-05 07:01:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: ea1a09547958b557a7f4a9087faa78ef SHA-1: 65bdd6446fa483454e57aa26bf24b7edc473ff5a SHA-256: df89d2793f5921c9d5d41fe2eae4158b22fabf19bbc9ec8f4585739b65ee790e
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains multiple external links, with one identified as an algorithmically generated URL pointing to a suspicious PDF file. The ML classifier and ClamAV detection strongly indicate malicious intent. The presence of external URIs and link farms suggests the document is used to redirect users to potentially malicious content, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9969

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
  • PDF link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://imagebrandstudio.com/userfiles/file/zajiweliro.pdf In PDF document text
    • http://drinkandshrink.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/161534edf8e06a---kilesevonimuxupere.pdfIn PDF document text
    • https://rallstarawards.us/nbloom/fckuploads/file/wipojigipakunog.pdfIn PDF document text
    • https://phatgiaolongan.com/upload/ckupload/files/98658666745.pdfIn PDF document text
    • https://intersensor.ro/v2011/Files/fck_upload/file/8058775283.pdfIn PDF document text
    • https://ppsu.cz/files/file/5845897387.pdfIn PDF document text
    • https://ccar.host168.com/data/fckeditor/files/loterigesisujevatugewuw.pdfIn PDF document text
    • http://xedaptap.net/userfiles/file/7703165298.pdfIn PDF document text
    • http://gespk.com/userfiles/file/mimelozoxe.pdfIn PDF document text
    • http://autoscuolapezzano.it/userfiles/files/76826757383.pdfIn PDF document text
    • http://dlshixiang.com.cn/ckfinder/userfiles/files/gavimumeparazikabukabo.pdfIn PDF document text
    • http://vasset.bg/userfiles/file/wenedepimudemenusowutaxes.pdfIn PDF document text
    • https://excore.hu/ckfinder/userfiles/files/35778899396.pdfIn PDF document text
    • https://hgindustrial.eu/userfiles/files/wusokigevoxev.pdfIn PDF document text
    • https://newfrio.com/userfiles/files/87898409704.pdfIn PDF document text
    • https://glosunspa.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ed1c6aaa99---kufexatetepemuvufoxibanaj.pdfIn PDF document text
    • http://carraracucinecomponibilitrapani.it/userfiles/files/2875300514.pdfIn PDF document text
    • http://profitoolinfo.ru/ckfinder/userfiles/files/vezamagaf.pdfIn PDF document text
    • https://interativacorretora.com/fotosempresa/files/36394238445.pdfIn PDF document text
    • http://bkht.vn/userfiles/file/76465338677.pdfIn PDF document text
    • http://nhatrangpalace.net/app/webroot/upload/files/37196723895.pdfIn PDF document text
    • http://northcity.rs/slike/files/kufisa.pdfIn PDF document text
    • http://slesnick.net/userfiles/files/96282130464.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=upstairs+downstairs+downton+abbeyPDF 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_off00010998.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10998 10688 bytes
SHA-256: 235a00dea4c69e5f02cff81d59c32f2d3d6fca50737b50b3c99f2ff5ba620474
font_01_sfnt_off00012217.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12217 19580 bytes
SHA-256: e7718fe0322686102dfd28448919b6dfb9abddb0af95e6af058743ca5d918fbb
font_02_sfnt_off000154ec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x154EC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1