Malicious PDF — malware analysis report

Static analysis result for SHA-256 79ae13f4d1ffb1fc…

MALICIOUS

PDF

86.9 KB Created: 2021-09-17 23:21:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 5f53d1b61fe03b0d8edb982418264968 SHA-1: f2f058a0e4c7fd04194a85de99a84032e4b73207 SHA-256: 79ae13f4d1ffb1fc0b445b6fda02b652e50864e19063eabe60b21f0902244139
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to compromised CMS uploads or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent. The embedded JavaScript likely facilitates the redirection to these malicious sites, which are designed to host phishing content or further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://synerhu.ru/uplcv?utm_term=the+hidden+oracle+read+online+pdf PDF link annotation
    • https://pbpkrosno.com/fckfile/45539147838.pdfIn PDF document text
    • https://www.albriug.com/static/editor/ckeditor/ckfinder/upfile/files/talawezotuzedebefutomeso.pdfIn PDF document text
    • http://archinfo.ru/uploads/file/palagafogimisupakarabuve.pdfIn PDF document text
    • http://bluebiz.kr/userData/board/file/8109656370.pdfIn PDF document text
    • http://dpnovelty.com/upload/files/magug.pdfIn PDF document text
    • http://korealabels.com/ckfinder/userfiles/files/kadaxuk.pdfIn PDF document text
    • https://38e5bbdfe8be.gdziezjesc.info/userfiles/file/naniwit.pdfIn PDF document text
    • http://microcement.ua/userfiles/file/ripusatam.pdfIn PDF document text
    • http://ventexevent.se/uploads/file/84106033272.pdfIn PDF document text
    • https://jdbailbonds.com/wp-content/plugins/super-forms/uploads/php/files/73fe6501527929a43ec25c1c8beaa5e9/90859674016.pdfIn PDF document text
    • http://zjnep.com/ckeditor/ckfinder/userfiles/files/84972116435.pdfIn PDF document text
    • https://carthink.org/wp-content/plugins/formcraft/file-upload/server/content/files/16130ce8776fb1---fukurekufakisiribet.pdfIn PDF document text
    • https://avenirpourtous.fr/wp-content/plugins/formcraft/file-upload/server/content/files/161375c4830494---dikigeka.pdfIn PDF document text
    • http://toyotaprius-custom.com/js/upload/files/98131764189.pdfIn PDF document text
    • http://karate-talence.com/newsite/userfiles/files/rimawazojekevoleritif.pdfIn PDF document text
    • http://patriabrno.cz/userfiles/files/88173428386.pdfIn PDF document text
    • https://prokoncept.hu/admin/blogfck/image/file/tavevudivox.pdfIn PDF document text
    • http://technoprofile.ru/userfiles/file/wadonawegowep.pdfIn PDF document text
    • https://pieseautocomenzi.ro/userfiles/file/doduvenudepu.pdfIn PDF document text
    • http://heatexchangersolution.com/upload_fck/file/2021-9-7/20210907174927639252.pdfIn PDF document text
    • https://classoft.ro/userfiles/file/befugumawuruwino.pdfIn PDF document text
    • https://somos.co/dleyes/admin/fotos/file/69185825921.pdfIn PDF document text
    • https://delphin-bau.com/ckfinder/upload/files/90589861889.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_off0000ee9a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE9A 18412 bytes
SHA-256: 3e133ae3e2ee5a4fca3f01b4187107fd9c4bb90a657147b4a1e8c5926f6dd77d
font_01_sfnt_off00011e70.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E70 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013687.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13687 10412 bytes
SHA-256: 1fb457af6877fbc941a65251e558073c328d455857c791da18870235ec166dfc