Malicious PDF — malware analysis report

Static analysis result for SHA-256 cf3a355a2bd880aa…

MALICIOUS

PDF

80.4 KB Created: 2021-09-17 17:21:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 4bdf66abdcff2cb6cee3f9a6d3319b58 SHA-1: 2397cca0be377bd94b6ca4aada2dcdf7b1c60b67 SHA-256: cf3a355a2bd880aa15fb142c515e9ec1b269ad8903d2e77f1f03e5a6599db60b
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ML and ClamAV as malicious, with heuristics indicating it functions as a link farm. The presence of numerous embedded URLs, many pointing to disposable domains, suggests an attempt to redirect users to malicious content or phishing sites. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with a phishing or malware distribution lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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 https://hanakspotrebice.cz/eshop/ckfinder/userfiles/files/93166499161.pdf In PDF document text
    • http://progetec.org/userfiles/files/xugonep.pdfIn PDF document text
    • http://hoanhaochemical.com/uploads/files/9801702756.pdfIn PDF document text
    • https://senfina.top/uploads/files/wunedumevapekofo.pdfIn PDF document text
    • http://tv-sat.cz/userfiles/file/40256639390.pdfIn PDF document text
    • http://training-solutions.ro/wp-content/plugins/formcraft/file-upload/server/content/files/161430ae1448ce---20964928726.pdfIn PDF document text
    • https://www.colline-eternelle.com/ckfinder/userfiles/files/xuvinuf.pdfIn PDF document text
    • http://madinagirls.com/easydo%20v2.00/files/uploads/3280417632.pdfIn PDF document text
    • http://freeware-software-download.de/uploads/editor/file/laned.pdfIn PDF document text
    • https://omprintandpack.com/userfiles/file/66987250651.pdfIn PDF document text
    • http://sbsinternationalschool.org/userfiles/file/96622880372.pdfIn PDF document text
    • http://synagoge-stommeln.de/ckfinder/userfiles/files/gorofofedareroline.pdfIn PDF document text
    • https://franchiseharbor.com/files/files/26163754606.pdfIn PDF document text
    • http://newtarrytowndeli.com/uploads/files/ledobolukanenepizimufina.pdfIn PDF document text
    • http://strahyi.ru/images/file/12121153305.pdfIn PDF document text
    • http://uptownherndon.com/uploads/files/dadovexiretul.pdfIn PDF document text
    • http://xn--ob0bjxt9h99icicrvkksa421cwwp7hiv4d6a.com/ckfinder/userfiles/files/99382532343.pdfIn PDF document text
    • https://aromamarketing.md/img/files/zogizusuzofuxabi.pdfIn PDF document text
    • http://eskuvoiiranytu.hu/blog/file/84990228040.pdfIn PDF document text
    • https://aymexco.eu/ckfinder/userfiles/files/lijagitotowi.pdfIn PDF document text
    • https://preciseenergygroup.com/media/desivipozuw.pdfIn PDF document text
    • https://harteron.ee/userfiles/file/60945581239.pdfIn PDF document text
    • http://jinanxintiandi.com/userfiles/files/37929433469.pdfIn PDF document text
    • https://linardi.ru/files/file/zifosuw.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=music+mp3+player+apkPDF 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_off0000d734.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD734 10684 bytes
SHA-256: d36e64e021e7c7769a7eba0b2a5308a2ce7f4949a62e1f99cac497e9f182209b
font_01_sfnt_off0000efbe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFBE 16888 bytes
SHA-256: c6ecf560f942d3e53d76c250eef9220b8790da590276a1c1493f7ace1fa26f25
font_02_sfnt_off00011bed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11BED 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1