Malicious PDF — malware analysis report

Static analysis result for SHA-256 83f38df91133a78e…

MALICIOUS

PDF

83.8 KB Created: 2021-09-20 12:50:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: d95ff884e23b6cbc3d40ad60722dc681 SHA-1: 729af10454a75c4a382dba77c0d7ebc68730cfb9 SHA-256: 83f38df91133a78e7e0119dcd95c8fde24ec09aa14b17b659ff7ba272809ead5
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to compromised WordPress sites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with known malicious PDF campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://laborke.ru/uplcv?utm_term=app+to+watch+live+cricket PDF link annotation
    • http://palestraarkadia.it/userfiles/files/65324990518.pdfIn PDF document text
    • https://egyptsuntours.com/userfiles/files/72576337063.pdfIn PDF document text
    • http://lsneotek.com/ckupload/files/repopeserotivitipibapadap.pdfIn PDF document text
    • http://gyndoktors.de/ckfinder/userfiles/files/dojojatop.pdfIn PDF document text
    • http://kirks-pool.com/wp-content/plugins/formcraft/file-upload/server/content/files/161401451759f4---14470934063.pdfIn PDF document text
    • http://enotecagaribaldi.it/userfiles/files/11647704097.pdfIn PDF document text
    • http://studioego.cz/userfiles/file/55686690201.pdfIn PDF document text
    • http://mirembeestate.co.ug/wp-content/plugins/formcraft/file-upload/server/content/files/1614037b5e7568---siginav.pdfIn PDF document text
    • https://www.grandeprairie.org/wp-content/plugins/formcraft/file-upload/server/content/files/16131a49d43be6---54846059959.pdfIn PDF document text
    • http://asztalosweb.hu/userfiles/file/gufekuzi.pdfIn PDF document text
    • http://aquamedia.cn/ckfinder/userfiles/files/38050950630.pdfIn PDF document text
    • https://icbacademy.com/upload/files/joratox.pdfIn PDF document text
    • https://dragonexpressml.com/userfiles/files/15466680175.pdfIn PDF document text
    • http://giovanninociti.com/userfiles/files/4219383464.pdfIn PDF document text
    • http://88cpap.com/userfiles/files/97761319405.pdfIn PDF document text
    • http://vangphutai.com/images/uploads/files/44287088951.pdfIn PDF document text
    • http://huerural.com/uploads/image/files/vujevakitukiseb.pdfIn PDF document text
    • http://matonaklawfirm.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/95038287150.pdfIn PDF document text
    • http://britishcytology.org.uk/ckfinder/userfiles/files/riweta.pdfIn PDF document text
    • http://info56.ru/userfiles/file/36409305564.pdfIn PDF document text
    • http://harekatmemuru.com/images/Media/files/60164560947.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_off0000e32e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE32E 10424 bytes
SHA-256: 6b9f4d22d5c3085fc36f615180ca1a8914f54ab1054ef789ffe57ed7b9ac8ec0
font_01_sfnt_off0000fb10.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB10 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011322.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11322 17900 bytes
SHA-256: c539fdf03581c96dc25521c429a67fdf0fbf766a30416850c3a43d62f9e79f4f