Malicious PDF — malware analysis report

Static analysis result for SHA-256 52fc7e3cf43694e4…

MALICIOUS

PDF

81.4 KB Created: 2021-09-18 09:52:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: e8249048ff0f26d1577c0794d9f42211 SHA-1: 9879582fa17ed33a37a09da5dcc5521eaa3f894f SHA-256: 52fc7e3cf43694e40745766c801426b0b58621b4b3217a031be28567c1c26ccc
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains an embedded JavaScript stream and numerous external URIs, many of which are hosted on compromised WordPress sites or disposable domains, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution through these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9966

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://crysiq.ru/uplcv?utm_term=flash+firefox+android PDF link annotation
    • http://beta-rc.com/upload/files/80138732863.pdfIn PDF document text
    • http://personnelstrategies.net/userfiles/file/1628137559.pdfIn PDF document text
    • http://wintec-samu.hu/uploads/files/50642498747.pdfIn PDF document text
    • http://asckhn.com/acskhn/userfiles/file/13204693983.pdfIn PDF document text
    • http://fratellilongoni.com/userfiles/files/72986283601.pdfIn PDF document text
    • http://www.tsssport.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613aa642c3f7e---96147249454.pdfIn PDF document text
    • https://luxesystem.site/js/ckfinder/userfiles/files/xawifasuv.pdfIn PDF document text
    • https://firmabudowlanawalczak.pl/web/uploads/files/38651336435.pdfIn PDF document text
    • http://climacom.eu/userfiles/files/suvizexowavemewipuf.pdfIn PDF document text
    • http://radis-rrl.ru/userfiles/image/zokibejaxiki.pdfIn PDF document text
    • http://ikuma-car.com/js/upload/files/romozevuzu.pdfIn PDF document text
    • http://rancholasmonturaspremios.com/campannas/file/jaxupusezenozimujumuvo.pdfIn PDF document text
    • http://mtegl.wsystem.sk/userfiles/files/jarotegapeb.pdfIn PDF document text
    • http://elsped.hu/files/file/61680994795.pdfIn PDF document text
    • https://autoteam.in/ckfinder/userfiles/files/25008229188.pdfIn PDF document text
    • https://angkortaxiservice.com/userfiles/file/jalebitumexojomelabejeba.pdfIn PDF document text
    • http://villaturri.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132b5b335ab1---40500120248.pdfIn PDF document text
    • http://tsuiteru66.com/userfiles/file/dezina.pdfIn PDF document text
    • http://namngonviet.vn/user-/files/56248463554.pdfIn PDF document text
    • http://mirsistem.com/depo/sayfaresim/file/60827548543.pdfIn PDF document text
    • http://scantech3d.com/files/60214227289.pdfIn PDF document text
    • http://chagatea.ru/wp-content/plugins/super-forms/uploads/php/files/e5e798ce353939e76310f3d9f9e09bac/8493346991.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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000cc9b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC9B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e4a8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4A8 1840 bytes
SHA-256: e11639021ae82bc81d66597892112dbefd7f2cb67f426bbebb6fc3c29591e729
font_02_sfnt_off0000ed4b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED4B 19988 bytes
SHA-256: 2d2449e91ce526447544175be1806cad10fddc9367d8ea4cb890d446d38050c2
font_03_sfnt_off0001200c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1200C 10432 bytes
SHA-256: 047f3a09076dfb7620ecd9ccc52e012f5aae7c21c9edb3737b3f7ada5218a335