Malicious PDF — malware analysis report

Static analysis result for SHA-256 343ba64466c12243…

MALICIOUS

PDF

76.5 KB Created: 2021-09-03 03:04:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 2a8be80bb4e63fae49814fe6e5bee785 SHA-1: dff295e72224b89dba0552181fef8225f12a150b SHA-256: 343ba64466c12243cf2166a25ae0f6e2844473f21efa81110fb0039cfb78fda2
184 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 point to compromised websites or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of a 'Callback phishing phone lure' heuristic further indicates a potential scam or phishing attempt. The ML classifier and ClamAV detection strongly support the malicious nature of this file.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9901

Heuristics 8

  • 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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • 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://cructi.ru/uplcv?utm_term=transistor+circuits+book+pdf PDF link annotation
    • https://gberwanda.com/gbe/useruploads/blogs/files/13743160189.pdfIn PDF document text
    • http://sunil.kr/uploadfile/fckeditor/file/sifizoxoju.pdfIn PDF document text
    • http://www.stallionreadymix.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160ab8af4b45a4---nakenifepebalukas.pdfIn PDF document text
    • https://readxyz.org/wp-content/plugins/super-forms/uploads/php/files/782d6b30d6010cf62aa1bf94bd0ecefe/tibezibanojixegofimol.pdfIn PDF document text
    • http://gw73patriots.com/clients/1/1e/1ed986c9d410becccfd9995a8318e329/File/buduvago.pdfIn PDF document text
    • https://evg-prague.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16078ba73ba42e---92358080250.pdfIn PDF document text
    • http://www.mondzorgvesa-voorschoten.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160e5f241732c7---93067374332.pdfIn PDF document text
    • https://bankkartya.hu/js/ckfinder/userfiles/files/52480994095.pdfIn PDF document text
    • http://yjsyrj.com/userfiles/file/25508180242.pdfIn PDF document text
    • http://files.ibiza-ferien.de/file/fatuvetaxi.pdfIn PDF document text
    • https://best-turbos.com/wp-content/plugins/super-forms/uploads/php/files/71c89029856ab80d85889f891cdcab6a/50512871394.pdfIn PDF document text
    • https://protectname.xyz/whoisprivacy/userfiles/files/73520251438.pdfIn PDF document text
    • https://pensionatiitalianiinportogallo.it/wp-content/plugins/super-forms/uploads/php/files/11077a4cb5bf00fe6b74d5ff7729f8b6/jerexebogipoberoxaziken.pdfIn PDF document text
    • http://footstepfloor.com/upfiles/files/22648588345.pdfIn PDF document text
    • https://ketdoanbus.com/webroot/img/files/42999499647.pdfIn PDF document text
    • http://hawks79.com/clients/85064/File/basenurus.pdfIn PDF document text
    • http://skybuildinfraprojects.com/uploads/39763301370.pdfIn PDF document text
    • https://travelsafeway.com/userfiles/file/73849000165.pdfIn PDF document text
    • http://canavesiobruno-architetti.it/userfiles/files/91377097851.pdfIn PDF document text
    • https://cubic.is/userfiles/file/10343353971.pdfIn PDF document text
    • https://dangeloremodeling.com/nbloom/fckuploads/file/pafizebukazududug.pdfIn PDF document text
    • http://emilybarnes.com/DEVELOPMENT/VERSIONED/emilybarnes/trunk/sites/default/files/file/81503086923.pdfIn PDF document text
    • http://pumarecovery.com/userfiles/files/gexiwojizimunigavenovix.pdfIn PDF document text
    • http://st-communications.com/ckfinder/userfiles/files/rurimosodikoda.pdfIn PDF document text
    • http://www.bewegeninarnhem.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607a0b9d475d9---71642288610.pdfIn PDF document text
    • https://calldidocta.com/wp-content/plugins/super-forms/uploads/php/files/ca920d158d5bbadf92e33134aefa7cd4/68134366733.pdfIn PDF document text
    • http://kwik-it.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160c9590589342---84664603379.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_off0000ca8a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA8A 10728 bytes
SHA-256: b6597c79905d8eb021df07f112ed14d0669d82ac5c1073ada8519a89a6c1c0e8
font_01_sfnt_off0000e31b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE31B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000fb2d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB2D 15968 bytes
SHA-256: 25e6c40d571c24b9b9df3db6d799c5a47b36a2f2dc4bcfafc5fc58218d4fb41c