Malicious PDF — malware analysis report

Static analysis result for SHA-256 4e57abc80024d0c2…

MALICIOUS

PDF

81.1 KB Created: 2021-08-22 01:47:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 28c8fecc8bf393ba3434be2c0c84edf5 SHA-1: dbb56720f19b60394dfce7d97359b3aa3fcfab2f SHA-256: 4e57abc80024d0c2155803a3c381858a65bd2c41cee2e6be5b044e708c7a8fe9
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, indicating a high likelihood of malicious intent. It contains numerous external links, many pointing to compromised CMS uploads or disposable hosting, suggesting a link farm designed to redirect users to malicious sites. The presence of these links and the overall structure strongly suggest a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

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://vansuloi.com/uploads/userfiles/file/warovevimifoziwazadunod.pdf
    • https://accuratesearch.com/userfiles/file/rasizajotufajegike.pdf
    • http://accessiblevehicleservices.com/userfiles/file/fenigopakiganirebovagozu.pdf
    • http://tmtechvn.com/webroot/img/files/pilunotu.pdf
    • https://angkortaxiservice.com/userfiles/file/65129396371.pdf
    • http://xn--aknmedical-yub.com/uploads/file/85736658265.pdf
    • http://xaydunglenguyen.vn/upload/files/fc604c.pdf
    • https://ahi.com.ua/wp-content/plugins/super-forms/uploads/php/files/610931a1c788993560427e9489e8b86a/43137230963.pdf
    • https://www.officinadelgustoroma.com/wp-content/plugins/super-forms/uploads/php/files/f5bb5a1e466b8f9acf67cfc5b3930e8b/rujexezusunofewajov.pdf
    • https://afriqueitnews.com/wp-content/plugins/super-forms/uploads/php/files/171b89c63d640498040707436f3eac49/duvinamazaluginerivuxikun.pdf
    • http://www.opencalgary.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607bdfa393bef---37170227623.pdf
    • http://vce34.ru/attachments/file/13520729321.pdf
    • http://falerisztika.hu/tmp/rixijoko.pdf
    • https://christembassyromford.org/wp-content/plugins/super-forms/uploads/php/files/b1835ed9557a34de97e735a5b6e262f8/jiborevurogugure.pdf
    • http://xn--80aab8aioy.xn--p1ai/userfiles/file/28179961827.pdf
    • https://lllk.ru/wp-content/plugins/super-forms/uploads/php/files/574de93d3c103bad547dd1068a779a18/duwefimelanusupulunasufas.pdf
    • https://www.limratechnologies.net/wp-content/plugins/formcraft/file-upload/server/content/files/1607fd8dba4b7e---lidopilemivokegusu.pdf
    • http://firesecurity.sk/userfiles/file/domovolejoler.pdf
    • https://dichvuketoansg.com/luutru/files/24612111254.pdf
    • https://ajwatravel.com/wheelmarine/userfiles/file/48931637523.pdf
    • https://neksav.com/upload/ckfinder/files/84151115105.pdf
    • http://dentherapia.hu/files/file/38649788207.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=how+to+reset+insignia+fire+tv+remote
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000db48.bin
58f535bbbef2ca16903ccfdd2985a191c18914136005b87a90df34c77498b7ae
pdf-font-stream PDF embedded font (sfnt) at offset 0xDB48 10656 bytes
font_01_sfnt_off0000f3be.bin
a9b62d796f416c755b093de180e6b9b97d6c6525bc1e08e5e5d3fcdc0fb44192
pdf-font-stream PDF embedded font (sfnt) at offset 0xF3BE 16428 bytes
font_02_sfnt_off00011e82.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11E82 16792 bytes