Malicious PDF — malware analysis report

Static analysis result for SHA-256 882d1a8a370e6b99…

MALICIOUS

PDF

70.4 KB Created: 2021-09-28 02:59:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 8b138058da1922e1b404e63ea86338fb SHA-1: 72932ab45015ff58fcdb5dc768c3cfae197d500a SHA-256: 882d1a8a370e6b997ff902cf4bb2c78495935f47fce4a436e236b656a1d0a0d2
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external resources, many of which are hosted on disposable domains, indicating a link farm designed to obscure malicious intent. The ML classifier and ClamAV detection strongly suggest malicious activity, likely related to phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with attempts to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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 http://e-menu.hu/editor_up/70143978924.pdf In PDF document text
    • http://rewitex.pl/userfiles/file/nuxepugaxoligazupal.pdfIn PDF document text
    • http://kargo-box.com/uploads/files/suwokuviperidejesalimitub.pdfIn PDF document text
    • https://dgssu.com/upfolder/e/files/20210927155457.pdfIn PDF document text
    • http://gospodarstwotoporow.pl/uploaded/file/10898227156.pdfIn PDF document text
    • http://specialcats.nl/media/files/50537966446.pdfIn PDF document text
    • https://promaxsuspension.com/csmimage/file/nubemu.pdfIn PDF document text
    • https://ximatinhdongnai.com/app/webroot/files/images/pages/files/wisajenamexezaveba.pdfIn PDF document text
    • http://fairfresh.net/assets/admin/ckeditorimage/files/41886516347.pdfIn PDF document text
    • http://av72-reklama.ru/userfiles/file/1631386159777f25776ffa9076e44f.pdfIn PDF document text
    • http://ambulatorioveterinariocigliano.com/userfiles/files/82933079477.pdfIn PDF document text
    • https://dnm.tw/uploads/files/202109081628545632.pdfIn PDF document text
    • http://stattus.com/assets/file/rumowidiluwopolebuwutud.pdfIn PDF document text
    • http://opuspointpartners.com/ckfinder/userfiles/files/vavaxelovinebukijiji.pdfIn PDF document text
    • http://www.aamuhsv-madisonalumni.org/files/files/80763242618.pdfIn PDF document text
    • https://aep-tc.com/cache/fck_files/file/sosulegekifu.pdfIn PDF document text
    • http://compie.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16136789981d4e---56059087135.pdfIn PDF document text
    • http://hennel.hu/sources/elemek/file/4064168175.pdfIn PDF document text
    • http://ukonlinedirect.com/userfiles/files/kezuworifimuva.pdfIn PDF document text
    • http://mpwlawpa.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/juxibeni.pdfIn PDF document text
    • http://www.absolutecateringla.com/wp-content/plugins/formcraft/file-upload/server/content/files/161475f0eefd11---80513961207.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=cartoon+hd+apk+latest+version+2020PDF 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_off0000af3d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAF3D 17276 bytes
SHA-256: c17b585f6cd5d91cd9cbbfabf670ec446af1e98b1191c0fa7b4ed90c647768fe
font_01_sfnt_off0000daf0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDAF0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f307.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF307 10920 bytes
SHA-256: 4513774cdf24eb0d48620946c6e685fcce9d12b995523594ee4cad7f518be246