Malicious PDF — malware analysis report

Static analysis result for SHA-256 acf9931983d0b989…

MALICIOUS

PDF

82.2 KB Created: 2021-09-08 19:59:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: e927730d33f2f56d615bb174731b2b1e SHA-1: 98d4d948c67f349eb0f83a9d59b637d4fb54329a SHA-256: acf9931983d0b9899709b93e8e4697da360eec33265b6d64f7c87cac506c837a
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The file was detected as malicious by ClamAV and an ML classifier, with heuristics indicating it is a link farm on disposable hosting. Numerous external URLs are embedded within the PDF, suggesting a phishing or malware distribution attempt. The `PDF_SEO_DISPOSABLE_LINK_FARM` heuristic points to a tactic of using many low-reputation domains to obscure the true malicious destination.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://ipssecurityconsultants.com/ckfinder/userfiles/files/16899107217.pdf In PDF document text
    • http://abwhopewell.com/uploads/files/68087884320.pdfIn PDF document text
    • http://www.kindytennis.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613434b961bad---58201205788.pdfIn PDF document text
    • https://godparents4tz.org/home/god/public_html/ckfinder/userfiles/files/94910699767.pdfIn PDF document text
    • http://jingyilin.org/uploads/file/moxifokinar.pdfIn PDF document text
    • https://samngaimarble.com/html_upload/file/748635664.pdfIn PDF document text
    • https://staging-info.sharkovinkom.com/sharkovinkom.com/ckfinder/userfiles/files/madekepa.pdfIn PDF document text
    • http://agriturismolataggiasca.eu/userfiles/files/96788640591.pdfIn PDF document text
    • http://chia4kids.ru/ckfinder/userfiles/files/56363622888.pdfIn PDF document text
    • https://pasifikendustriyel.com/userfiles/file/85352279992.pdfIn PDF document text
    • https://designmaster.in/scgtest/eec-new/codelibrary/ckeditor/ckfinder/userfiles/files/rodiv.pdfIn PDF document text
    • http://exactblue.com/wp-content/plugins/formcraft/file-upload/server/content/files/161363e52df698---57619323518.pdfIn PDF document text
    • https://delta-relay.be/userfiles/file/29779249535.pdfIn PDF document text
    • https://altaitur.com/ckfinder/userfiles/files/kuwebudufajovejux.pdfIn PDF document text
    • https://www.aifimm.it/admin/inc/ckfinder/userfiles/files/bafemi.pdfIn PDF document text
    • http://superlitefan.com/uploads/files/34690381059.pdfIn PDF document text
    • http://chinawin-consult.com/userfiles/38043989175.pdfIn PDF document text
    • http://shinyoungvalve.com/userData/board/file/mabotaderaterepez.pdfIn PDF document text
    • http://portaldeaquidauana.com.br/ckfinder/userfiles/files/woxuwa.pdfIn PDF document text
    • http://tvoirostov.ru/ckfinder/userfiles/files/minazubegokemigobixusuti.pdfIn PDF document text
    • http://mexvp.com/ckfinder/userfiles/files/8948001775.pdfIn PDF document text
    • https://suprizpin.com/calisma2/files/uploads/suxabo.pdfIn PDF document text
    • https://trickapotisk.cz/webpagebuilder/ckfinder/userfiles/files/26822261775.pdfIn PDF document text
    • http://denkobarbell.com/_upload/files/piradoboruset.pdfIn PDF document text
    • http://chaodontuonglai.vn/uploads/ck_upload/files/gawekewaz.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=vancouver+island+map+pdfPDF 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_off0000d919.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD919 18852 bytes
SHA-256: ca4f24192deb5d811631453536dca94de4909ea3b6817699825d854550180c53
font_01_sfnt_off00010a18.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A18 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001222f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1222F 10820 bytes
SHA-256: 25c312dd5fb671f9c4431ef9082505c5b7d9b1ebd6bfa6d415f1bb8da24fe4a6