Malicious PDF — malware analysis report

Static analysis result for SHA-256 23574335a63604e1…

MALICIOUS

PDF

74.2 KB Created: 2021-10-08 01:04:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-20
MD5: 3cab5898633bd85ff7f3a1135972eb8f SHA-1: 23d0ecec5fdb4ec6c54c64d75f31b418fb687b7b SHA-256: 23574335a63604e190933b157ed9525f5c8260ec5d9e1619df7058e5d1ce4680
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and a machine learning classifier indicated a high probability of maliciousness. The document contains numerous external URIs and links to compromised CMS upload storage, suggesting it functions as a link farm. The primary purpose appears to be directing users to potentially malicious websites, likely for phishing or malware distribution, as indicated by the presence of multiple disposable hosting links and UTM parameters.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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 farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://pistant.ru/uplcv?utm_term=funny+pranks+to+do+at+home PDF link annotation
    • http://www.infranetltd.com/wp-content/plugins/formcraft/file-upload/server/content/files/161400d588848e---15205983909.pdfIn PDF document text
    • http://www.shipsupply.co.mz/wp-content/plugins/formcraft/file-upload/server/content/files/1614870b9a1eba---81980611810.pdfIn PDF document text
    • http://kultura-vyazniki.ru/sites/default/files/file/pisorenopokavitute.pdfIn PDF document text
    • http://humansharehouse.com/userData/board/file/73554852364.pdfIn PDF document text
    • http://em-ail.ch/pictures/2/85701000869.pdfIn PDF document text
    • http://ventensis.lt/public/ckfinder/userfiles/files/venelenepakudij.pdfIn PDF document text
    • https://bloodyofficeadmin.underguide.com/upload/userfiles/file/benase.pdfIn PDF document text
    • https://frontiermyanmar.com/sites/all/libraries/ckfinder/userfiles/files/7930916569.pdfIn PDF document text
    • http://lamorenj.com/userfiles/files/42635467687.pdfIn PDF document text
    • http://nsfeed.com/_UploadFile/Images/file/rodogenej.pdfIn PDF document text
    • https://obrbikes.com/files/files/jarokifozezodawelozizix.pdfIn PDF document text
    • http://velapower.com/glwh/UploadFile/file/2021092905002173499.pdfIn PDF document text
    • https://es21sys.com/userfiles/file/82888829835.pdfIn PDF document text
    • https://qfuse.it/images/uploaded_files/ckfinder/files/1631706650_b5ed5bbd63.pdfIn PDF document text
    • http://mijneigenlift.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16140871268cc4---risifulolos.pdfIn PDF document text
    • http://mamaskitchenorder.com/uploads/files/8636966976.pdfIn PDF document text
    • http://kowalstwwo.pl/public/cms/images/file/wibugosidalejufanonugik.pdfIn PDF document text
    • https://volpatoebrum.com.br/_common/admin/scripts/ckfinder/userfiles/files/xanuduxo.pdfIn PDF document text
    • http://mgmkt.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161508bd26bc6d---86743226195.pdfIn PDF document text
    • http://songhandiban.com/uploadfile/file/2021091623482973499.pdfIn PDF document text
    • https://b7b.reviewz.eu/app/webroot/files/userfiles/files/teluja.pdfIn PDF document text
    • https://himalayanthailand.com/image/upload/File/25446505858.pdfIn PDF document text
    • http://zeshengtecphar.com/UploadFiles/FCKeditor/20210913110419.pdfIn PDF document text
    • http://scales-center.com/shop/fck_file/file/dupiweke.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_off0000c0a6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC0A6 16452 bytes
SHA-256: 667a0eae0537e91f3442047003bcdc671a09d79523d261bc99a2059752b2e115
font_01_sfnt_off0000eabe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEABE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000102d5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102D5 10800 bytes
SHA-256: 5c245c13713a997daa1f125d155ed434f48a3bcc8fed68240c49e9611b31cef1