Malicious PDF — malware analysis report

Static analysis result for SHA-256 68a436b6fcafafe3…

MALICIOUS

PDF

77.5 KB Created: 2021-08-01 01:48:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 393c152c48b12b7bc63e27fda83243f4 SHA-1: fb2fa1eb5601128b37ce01f1d9c6a131c70acc45 SHA-256: 68a436b6fcafafe37b92ae6b3d8aaf43bddecf61e38067f5566396b6f519a143
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs that form a link farm, with many pointing to compromised WordPress sites or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The presence of external URIs and link farms suggests an attempt to lure users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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://krisoc.ru/uplcv?utm_term=alvin+and+the+chipmunks+1+free+download PDF link annotation
    • http://vhs1962.com/clients/b/b9/b967f936f519796c2a696a6ed1da67f9/File/8560727434.pdfIn PDF document text
    • https://www.isgs.org/wp-content/plugins/super-forms/uploads/php/files/de4d535aa274adbcde6de0c470bc144c/83850090778.pdfIn PDF document text
    • http://kingspec.su/wp-content/plugins/super-forms/uploads/php/files/bdb9mr55c94ckst8c105cbviut/sidulavirenepuzefuk.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/16092e822c4ad8---87459417727.pdfIn PDF document text
    • https://lightupalife.org.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160758043ad6de---87160137062.pdfIn PDF document text
    • http://lifestyleufa.ru/wp-content/plugins/super-forms/uploads/php/files/b9fbbbc4b1b8017b4becb4ad8967a21d/45927692398.pdfIn PDF document text
    • https://rhythmcprandfirstaid.com/wp-content/plugins/super-forms/uploads/php/files/1d0fb83b44596d78f5433563b536ef0f/tatejegotopesobexizobife.pdfIn PDF document text
    • https://info-jimukyoku.jp/lot/upload/files/24150994763.pdfIn PDF document text
    • http://hotstamping.pl/files/file/61549094220.pdfIn PDF document text
    • https://wills.sg/wp-content/plugins/super-forms/uploads/php/files/4c4af50844a994baf7c63470348b0b5c/tasuxagarox.pdfIn PDF document text
    • https://xn--78-6kce7dfhb9dwb.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/5e83ef8f491fdf0e657457e89c53ae2a/gavepuw.pdfIn PDF document text
    • http://www.carolglassman.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607730fa162bd---74353794359.pdfIn PDF document text
    • http://www.hypnotiseur.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bd47ddd89c1---barolavadumer.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087ffabb7c97---fowesir.pdfIn PDF document text
    • http://nenorm.com/files/files/jopezaxuzi.pdfIn PDF document text
    • http://www.musicmaestrodiscos.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160773da0477ac---96711770353.pdfIn PDF document text
    • https://qamarapps.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a0bf3e1303a---34426848708.pdfIn PDF document text
    • http://mirrorgallery.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d62c815982b---74923684488.pdfIn PDF document text
    • http://logo4you.dk/userfiles/file/94787998427.pdfIn PDF document text
    • http://www.julitolaschools.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c49b8ad8d95---vugifetesojit.pdfIn PDF document text
    • https://www.hinogas.com/wp-content/plugins/super-forms/uploads/php/files/ijg6flllelshhtk7f6dnqetifk/91319661757.pdfIn PDF document text
    • http://www.kocay.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160bc80300ab8a---21621544016.pdfIn PDF document text
    • http://imagespa.mx/wp-content/plugins/formcraft/file-upload/server/content/files/160a0205bb8e4f---zobuzipeziparolewiwaz.pdfIn PDF document text
    • http://victoryelectricalsupply.com/ckfinder/userfiles/files/36598213191.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_off0000ca42.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA42 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e259.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE259 11260 bytes
SHA-256: b48a594732c93f2db8b110c302f21572a9b9fc24e2efa3e2f3f871e4db507a70
font_02_sfnt_off0000fca3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFCA3 16524 bytes
SHA-256: 0cc9468df30448139ded772df733350b7f9a647c2937fd97f0866bffe754efa3