Malicious PDF — malware analysis report

Static analysis result for SHA-256 77d6443bd888cd55…

MALICIOUS

PDF

67.0 KB Created: 2021-10-01 06:38:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 62e8523f272702082de90af255e96285 SHA-1: c2aa11d16fcce131cfad2ae2846735a1e8cf3411 SHA-256: 77d6443bd888cd55ba3f4e28f0cb522ba49c17a153f2ef5a5cf3282f1640428e
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document exhibits characteristics of a phishing or malware distribution lure, as indicated by the high number of external URLs and the ClamAV detection as 'Pdf.Phishing.Trojan'. The ML classifier also strongly flagged this PDF as malicious. The presence of numerous links, many pointing to disposable domains or link farms, suggests an attempt to direct users to malicious sites for credential harvesting or malware download.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://catamma.ru/uplcv?utm_term=play+audio+and+video+in+android PDF link annotation
    • http://abw10thstreetne.com/uploads/files/49945062109.pdfIn PDF document text
    • https://peiitw.com/Upload/ckeditor/files/75100918005.pdfIn PDF document text
    • http://murielbellhomes.com/userfiles/files/40518904808.pdfIn PDF document text
    • http://sh-songshi.com/admin/upimg/file///tufus.pdfIn PDF document text
    • http://amwordpress.org/wp-content/plugins/formcraft/file-upload/server/content/files/1613e13030ece0---23778830954.pdfIn PDF document text
    • http://xn--h1agcmh.com/ckfinder/userfiles/files/93746902162.pdfIn PDF document text
    • http://finara-v.com/file_media/file_image/file/16650940962.pdfIn PDF document text
    • http://trevelci.ru/ckfinder/userfiles/files/30999814357.pdfIn PDF document text
    • http://matraholding.hu/images/userfiles/files/fituwajegax.pdfIn PDF document text
    • http://volker-issmer.de/userfiles/file/kefapegedujorerizowub.pdfIn PDF document text
    • http://studiopiergentili.it/userfiles/files/84595626346.pdfIn PDF document text
    • http://am-assets.com/aom/magnolia/userfiles/file/zurewigesubilenijumamexi.pdfIn PDF document text
    • http://mgocsm.in/userfiles/file/88964404239.pdfIn PDF document text
    • https://tipresentoio.it/images/file/39406565715.pdfIn PDF document text
    • http://z-i-f.ru/userfiles/file/zigavitufodibukozu.pdfIn PDF document text
    • http://musicpark-live.de/userfiles/file/lewoliwutemokemu.pdfIn PDF document text
    • http://eakqshop.com/ckfinder/images_store/files/76183410310.pdfIn PDF document text
    • https://e2imgu.ratnatelenet.com/UserFiles/file/28415010696.pdfIn PDF document text
    • https://chingchia.com/uploads/files/202109290833127582.pdfIn PDF document text
    • http://www.sunarnuricomuisvealisverismerkezi.com/wp-content/plugins/super-forms/uploads/php/files/20cp8fml9ba8gq2rttj1r4mdp6/bifedajomixenamejas.pdfIn PDF document text
    • http://kommunikator.nu/demo/userfiles/file///dinap.pdfIn PDF document text
    • 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_off0000aab2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAAB2 14712 bytes
SHA-256: ea8f1fcf0285eca3a30813b03d598596a00abe00a1bf5b0d0a5393c84e598316
font_01_sfnt_off0000cf94.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF94 10256 bytes
SHA-256: 79c36a70ac844b3a37260224ad914b4103f59ddaee7cb254bf21c23459c5f5ab
font_02_sfnt_off0000e6b5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6B5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1