Malicious PDF — malware analysis report

Static analysis result for SHA-256 c825fd74f3ba13e2…

MALICIOUS

PDF

71.7 KB Created: 2021-10-06 11:03:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 52ee349759a05b1b1d4b5c0d0399a009 SHA-1: b418432b2df491925cc2da198ee87ed4810acfa9 SHA-256: c825fd74f3ba13e28fa4127ef2a747a289afc4c75240ffd4e9d8eaf259431b15
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. Heuristics indicate the document functions as a link farm, directing users to multiple external websites, some hosted on compromised CMS platforms. The embedded URLs and the nature of the heuristics suggest the primary goal is to redirect users to potentially malicious content or phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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 http://rucodelniza.ru/userfiles/file/67482968061.pdf
    • https://instalacje-elektryczne.net/ckfinder/userfiles/files/73792127973.pdf
    • https://tgvl.in/uploads/fck/files/xonibujemoruxu.pdf
    • https://www.sensiblemachines.com/ckfinder/core/connector/php/files/68136308422.pdf
    • http://namdolove.com/FileData/ckfinder/files/20210906_2EC0B470E5C1A10F.pdf
    • https://allianztc.ro/files/file/rubozaxip.pdf
    • http://www.arborvitae.cz/ckfinder/userfiles/files/96009076424.pdf
    • http://northamericaminingexpo.mininglifeonline.net/file/f89BvudI6RSIgWIT.pdf
    • http://www.cascinasorigherio.it/wp-content/plugins/formcraft/file-upload/server/content/files/16158709e53e10---68504559898.pdf
    • http://kythuatviet.vn/uploads/userfiles/file/disikisixuji.pdf
    • http://hanboo.cn/Uploads/file/2021092804460170554.pdf
    • https://francois-daulte.com/ckfinder/userfiles/files/81739876414.pdf
    • http://www.stockholmswingallstars.com/wp-content/plugins/formcraft/file-upload/server/content/files/161339f5f1007a---katerupifoletolur.pdf
    • http://carrozzeriardue.it/userfiles/files/92674391099.pdf
    • https://elitestrategyglobal.com/wp-content/plugins/super-forms/uploads/php/files/058e9a67741d3ee5d7c679b9eef44aa9/95387376196.pdf
    • https://fsreloading.com/userfiles/files/93858932899.pdf
    • http://joshuadacosta.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134236626b7a---xukuwuxugogutiwew.pdf
    • http://itena.si/uporabnik/file/wutegulafeb.pdf
    • http://bronnicy.inhome360.ru/admin/ckfinder/userfiles/files/36679842377.pdf
    • http://montaze.org/democms/userfiles/file/9191643414.pdf
    • http://thesecurityguardunion.ca/userfiles/files/wasamizamewefexe.pdf
    • http://ocung.net/img/files/71232062388.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=mitochondria+provides+energy+in+the+form+of
    • 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_off0000b625.bin
08ad39a6f150114cc193bad54408e0becb0f085a37fae04dc6dcaf17ee5dd195
pdf-font-stream PDF embedded font (sfnt) at offset 0xB625 16232 bytes
font_01_sfnt_off0000deff.bin
5ba8b37e0bb03a5f78cfb39af76598bc1a86d143d3495aac8504f7a78bfa3ba9
pdf-font-stream PDF embedded font (sfnt) at offset 0xDEFF 11196 bytes
font_02_sfnt_off0000f8de.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF8DE 16792 bytes