Malicious PDF — malware analysis report

Static analysis result for SHA-256 55c6479796392ac6…

MALICIOUS

PDF

77.5 KB Created: 2021-06-26 02:00:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c1931d2bcd660b8c508cb75ec91ac7b6 SHA-1: a8f9dfbd955f036816ab53e23dd13ad896c3cae7 SHA-256: 55c6479796392ac6c8c9f5fa9f154d6c9f15e480883b6269d5e3c57ee3c0a297
156 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and by an ML classifier as malicious. It contains numerous external URIs and link farm patterns, indicating an attempt to redirect users to potentially malicious websites. The presence of compromised CMS upload links further suggests a malicious intent to host or distribute further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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://irlanc.ru/uplcv?utm_term=shae+game+of+thrones
    • http://market-oborudovanie.ru/upload/file/27399921211.pdf
    • https://viajespereira.com/wp-content/plugins/formcraft/file-upload/server/content/files/160849be99566f---jatinifile.pdf
    • http://asirius.su/wp-content/plugins/super-forms/uploads/php/files/50690add8749b203510223447138c828/50913324919.pdf
    • https://celovechurch.org/wp-content/plugins/super-forms/uploads/php/files/8f08f8599f1cba34db39b7d704d18bea/72510469928.pdf
    • https://go2germany.ru/files/file/kuxapesumuto.pdf
    • http://escolacaritas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a6636650f88---62830373832.pdf
    • https://altinhediyeler.com/calisma2/files/uploads/56146020183.pdf
    • https://forumhotel.by/wp-content/plugins/super-forms/uploads/php/files/7u6btbb6umpa395tasv9ibbmk0/dorogufanegetasixu.pdf
    • https://www.brunosistemi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a05694b9a0---48552956773.pdf
    • https://wfca-czech.cz/temp/userfiles/files/bekikumijijago.pdf
    • http://purpledoorchurch.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086264bec981---xovirawidirilinivenabilew.pdf
    • https://arenda1s.ru/wp-content/plugins/super-forms/uploads/php/files/307800bfd4e3f867e5d01b815651d7fa/11542365684.pdf
    • https://unitedcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a83beb757f4---xafafodagivitixudo.pdf
    • http://easternsheep.by/app/upload/file/suxefivekebopo.pdf
    • https://www.fecomerciomg.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/160995c4035e8e---87091713767.pdf
    • http://msslink.ru/userfiles/files/kafife.pdf
    • http://pferdefreunde-brueckenhof.de/sites/default/files/userfiles/file/14747302093.pdf
    • http://gsoam.ge/wp-content/plugins/formcraft/file-upload/server/content/files/1608c807e9d89b---3221437794.pdf
    • https://freedomhypnosisnyc.com/wp-content/plugins/super-forms/uploads/php/files/e57a9665001653dc04cf930d3c9186c6/bukijuli.pdf
    • https://anup.bo/images/files/maponetixapufajeporevux.pdf
    • https://www.webhisto.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160c45e55587ab---88429825107.pdf
    • http://staresecurity.com/userfiles/file/49193993432.pdf
    • http://www.petersmetalstitching.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1608634a48eb85---63752732381.pdf
    • https://myupfield.link/wp-content/plugins/super-forms/uploads/php/files/p0pi38g35633k4t8su1ne7r056/40331746072.pdf
    • 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_off0000cb6b.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xCB6B 16792 bytes
font_01_sfnt_off0000e37d.bin
cd4f2a3b60dfb877cbb2929e70a1dab6082f56cd2eacef85b387be4feedda67e
pdf-font-stream PDF embedded font (sfnt) at offset 0xE37D 17460 bytes
font_02_sfnt_off0001113d.bin
30c7e6003885db9a2124ab8a23cf4041316f73e17fcdc28a99668a5e514d12d5
pdf-font-stream PDF embedded font (sfnt) at offset 0x1113D 10600 bytes