Malicious PDF — malware analysis report

Static analysis result for SHA-256 cd53ef525672277e…

MALICIOUS

PDF

111.0 KB Created: 2021-09-04 10:13:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 49b4c0cb9aa83211f5a4ab4ab0faf348 SHA-1: d397d4df2389b94a3aa487447224b61876e5aa6d SHA-256: cd53ef525672277ebc4f9713075bae221097c2d9b1feea60c8bd182bfc50dd39
156 Risk Score

Malware Insights

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

The PDF contains a large number of links, many pointing to compromised WordPress upload directories, indicating a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution via these links. No scripts were extracted, but the structure and URL heuristics point to a common distribution method for malicious PDFs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9780

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://festivalecolo.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1608e69a00e4ec---fedulejufemade.pdf In PDF document text
    • https://www.tzounakos-insurance.gr/ckfinder/userfiles/files/rovipijexagu.pdfIn PDF document text
    • https://lnpro.in/ckfinder/userfiles/files/lesijeve.pdfIn PDF document text
    • https://kabelkyaobuv.sk/editor_uploads/files/41423701845.pdfIn PDF document text
    • https://mudateconmigo.cl/wp-content/plugins/super-forms/uploads/php/files/886afb064bfa0a776c40d3250008b669/35132466793.pdfIn PDF document text
    • https://31app.com/userfiles/file/suwibavo.pdfIn PDF document text
    • https://rjiminfra.com/wp-content/plugins/super-forms/uploads/php/files/adf21af6a85cb70ab903012a268a4e2a/39612432279.pdfIn PDF document text
    • http://quocteanviet.com/img-chamthi/files/87811420022.pdfIn PDF document text
    • https://www.capitalroofingct.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c5929c4ad0d---delidajipepujafoxikixo.pdfIn PDF document text
    • https://sakitonus.ru/wp-content/plugins/super-forms/uploads/php/files/21a326bb7b78ec23785a4237067abfbe/7437283081.pdfIn PDF document text
    • http://stihoplet.by/upload/editor/files/jafivo.pdfIn PDF document text
    • http://kondicionery-dolgoprudny.ru/upload_picture/file/lukubasijejenopebepixedev.pdfIn PDF document text
    • http://nzmbc1611.com/clients/e/e6/e6eb4f38db7021b04b945082fca6026d/File/kenajefilotaze.pdfIn PDF document text
    • http://ipvoicenj.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d1ad5d3ce2d---76471545266.pdfIn PDF document text
    • http://bikipvuikhoedep.com/app/webroot/files/editor_upload/files/62254284564.pdfIn PDF document text
    • http://meandnetworking.com/ckfinder/userfiles/files/1018861595.pdfIn PDF document text
    • http://www.segurosfacility.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609f0ea6826b3---8092169681.pdfIn PDF document text
    • http://tencanpowder.com/d/files/zaxut.pdfIn PDF document text
    • https://damiel.eu/userfiles/file/23569809271.pdfIn PDF document text
    • https://maconlux.lu/userfiles/files/19334481150.pdfIn PDF document text
    • http://luvnchrlysenglishtoys.com/clients/861429/File/motugirezesekak.pdfIn PDF document text
    • https://buddingheights.org/wp-content/plugins/formcraft/file-upload/server/content/files/160d23dcaea389---91163451012.pdfIn PDF document text
    • http://emke.hu/uploads/ckfinder/userfiles/files/vofinukawanoxexeratupo.pdfIn PDF document text
    • http://skolicka.eu/foto/images/file/83484600292.pdfIn PDF document text
    • https://accesoriosalmayor.com/images/userfiles/file/37884132014.pdfIn PDF document text
    • http://esen.life/userfiles/file/pinoxoxukozawafigagufi.pdfIn PDF document text
    • http://antasboru.com/guvennet/resimlerfiles/mowatisiroxevepizopekem.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=homelite+log+splitter+ut49103+manualPDF link annotation
    • 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_off0001466b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1466B 19540 bytes
SHA-256: fe9954e816a647799d0ece86b92128f05b9d1ba9d7a58944b1f7a38fd0e77867
font_01_sfnt_off000179cc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x179CC 11276 bytes
SHA-256: ce0ae00cc519fa3356bb1df1737c0ac93c567bdda30553d014fb2db14b2b62d3
font_02_sfnt_off0001944d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1944D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1