Malicious PDF — malware analysis report

Static analysis result for SHA-256 8508c665255bb585…

MALICIOUS

PDF

75.3 KB Created: 2021-09-18 18:05:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 8479bcfd0def93f8efd2f081a5d9e287 SHA-1: 15c7295a4479508f8b2b90f771f4593779926ff1 SHA-256: 8508c665255bb585f0f027266268c03c24b645ae1c85c0c21257f97e8f039721
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file contains numerous embedded URLs, many of which point to compromised websites or domains associated with link farms. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to lure users to phishing sites or download further malicious content. The presence of multiple distinct hosts and the use of UTM parameters suggest an attempt to track user engagement with these malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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 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://medvor.ru/uplcv?utm_term=dream+soccer+mod+apk PDF link annotation
    • http://fitviewer.biz/files/file/28588773482.pdfIn PDF document text
    • http://xetaihyundai.net/upload/files/70558393855.pdfIn PDF document text
    • http://www.siscard.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614119d509c5a---13162321929.pdfIn PDF document text
    • https://aiaciran.org/cache/fck_files/file/lixuvukirolumoliz.pdfIn PDF document text
    • https://www.cir.cloud/wp-content/plugins/formcraft/file-upload/server/content/files/16141ab5125809---94092845873.pdfIn PDF document text
    • http://hexindechem.com/upload/files/kowawolite.pdfIn PDF document text
    • http://controldellaves.com/app/webroot/arxius/file/kufikavunalotonuxizatoli.pdfIn PDF document text
    • http://www.iuoelocal870.com/kaizen/ckfinder/userfiles/files/56950278446.pdfIn PDF document text
    • http://www.dadosefatos.net.br/wp-content/plugins/formcraft/file-upload/server/content/files/161326550e5f02---89686922476.pdfIn PDF document text
    • http://ediliziaunoaventi.com/userfiles/files/walitebubimotakijavugosa.pdfIn PDF document text
    • https://pre-www.bridge-college.com/uploaded/ckeditor/files/fasasew.pdfIn PDF document text
    • http://khachsanmyngoc.com/upload/files/66101870283.pdfIn PDF document text
    • http://onlinetradeshow.ir/uploads/files/tinifolavokivamaga.pdfIn PDF document text
    • http://www.sport-konyv.hu/userfiles/file/devekaxamadimotosujabup.pdfIn PDF document text
    • http://standdominica.org/files/files/wovenam.pdfIn PDF document text
    • https://worldmedglobal.com/userfiles/files/91869351401.pdfIn PDF document text
    • http://www.medic-pneumolog.ro/fisiere/file/96378607963.pdfIn PDF document text
    • http://nt-module.ru/ckfinder/userfiles/files/zawujilotufused.pdfIn PDF document text
    • https://hirurgija.me/files/geliwani.pdfIn PDF document text
    • https://copacndg.com/images/uploads/files/84932876474.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_off0000c6db.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC6DB 10428 bytes
SHA-256: a0620d89c8c3cfb0f8dfa7b8af162902c75598f1bf86499a82ecb6c4b2d828ab
font_01_sfnt_off0000de80.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE80 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f692.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF692 16228 bytes
SHA-256: 1324942ca2ade7efe00800768de44a72a84efa4a855f4bc2b46dd128b9538bbb