Malicious PDF — malware analysis report

Static analysis result for SHA-256 8acd9681a404ea68…

MALICIOUS

PDF

79.3 KB Created: 2021-09-08 22:45:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: f3a33ac34bf3753076faf23f3f6e96a4 SHA-1: e648989e4cb7fee195dcc09deaf05cbe74c03952 SHA-256: 8acd9681a404ea68c750e67f6952f38e0b240d27c1a43877ea11fccdeb60afaf
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains numerous embedded URLs, many of which are part of a link farm hosted on disposable domains, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. Although no scripts were explicitly extracted, the PDF structure and embedded URIs are indicative of a malicious document designed to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://krisoc.ru/uplcv?utm_term=mixmeister+for+android PDF link annotation
    • http://actlogistic.vn/upload/editor/files/87896372732.pdfIn PDF document text
    • https://maychieuvinh.vn/upload/files/fidegamejepujanezajud.pdfIn PDF document text
    • http://gonvvama.net/filespath/files/20210904062420.pdfIn PDF document text
    • http://glamour-nsk.ru/ckfinder/userfiles/files/vejevelumudodepigeferadi.pdfIn PDF document text
    • http://ahzgbh.news-read.com/upload/files/70192273507.pdfIn PDF document text
    • http://baschin-heizung.de/meineBilderAlbertGrundschule/file/womomutofi.pdfIn PDF document text
    • http://strojsteel.cz/webpagebuilder/ckfinder/userfiles/files/serazuk.pdfIn PDF document text
    • https://amigo-shop.105h.net/upload/files/15611163568.pdfIn PDF document text
    • http://medicaldistri.com/ckfinder_files/files/gujaguxosopoxewen.pdfIn PDF document text
    • http://robwalker.net/fckupload/file/12600117120.pdfIn PDF document text
    • http://hferrynetworks.com/FileData/ckfinder/files/20210908_A9A2BE18DAF24ADE.pdfIn PDF document text
    • http://xn--pr3b03lcdvwu9dpynqkc.com/DATA/file/20210905130111.pdfIn PDF document text
    • http://www.look4job.gr/images/_user_na/file/xuzitin.pdfIn PDF document text
    • http://xn----itbbfrdrdbd4bgy6gi.xn--p1ai/webroot/files/files/14715727109.pdfIn PDF document text
    • http://760_709737661.mildmedia-dev.eu/uploads/userfiles/files/xexotekexovaduxerorilepe.pdfIn PDF document text
    • https://hotelpancharatna.com/assets/userfiles/files/romokipekagakomulixejiw.pdfIn PDF document text
    • https://carcarnet.com/home/sandbox/domains/hkdance.tritek.hk/public_html/ckfinder/userfiles/files/rabotitamipuxe.pdfIn PDF document text
    • https://www.osteopathe-montpellier-sud.fr/ckfinder/userfiles/files/26356171576.pdfIn PDF document text
    • http://pascalparrot.com/uploads/assets/file/90729749804.pdfIn PDF document text
    • http://mq-water.net/upload/58736633863.pdfIn PDF document text
    • https://eurosan.pl/user_images/file/65604160418.pdfIn PDF document text
    • https://smartstone.ca/userfiles/files/27742774362.pdfIn PDF document text
    • https://ans5680.preneed91.com/upload/files/peweka.pdfIn PDF document text
    • https://yam-token.com/business_school/uploads/file/62993083179.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_off0000cf11.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF11 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e728.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE728 10564 bytes
SHA-256: 3095d1256275fd2f7e0273931bb275716e79680b3901a786778b6123f86722c3
font_02_sfnt_off0000ff43.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF43 19112 bytes
SHA-256: 7612d6c6a7ff5a3750127864edf907edc481b1da68b5bf86eaab8501b50d69d8