Malicious PDF — malware analysis report

Static analysis result for SHA-256 4b09bac08a533404…

MALICIOUS

PDF

80.0 KB Created: 2021-09-01 17:48:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 8e0f9f42afd096e25906f9ab3e90ec3b SHA-1: bca92d6b2f444f5a0fda0ea0eeee364668ecda6c SHA-256: 4b09bac08a53340469e65ced669d571db11e5f9c00ff1939a1198a65b751ee46
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised WordPress upload directories, suggesting a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9989

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 http://cgt-fo-csc.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1611e1f2fa8305---11119437791.pdf In PDF document text
    • https://accesoriosalmayor.com/images/userfiles/file/fitojadenitef.pdfIn PDF document text
    • http://cityclick.it/userfiles/files/70841414652.pdfIn PDF document text
    • http://countrysquirefoods.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d038ea47a0---3328438446.pdfIn PDF document text
    • https://rpitrade.com/ckfinder/userfiles/files/pagirikam.pdfIn PDF document text
    • http://sochi-polyana.com/ckfinder/userfiles/files/46452903413.pdfIn PDF document text
    • https://2greenchicks.com/wp-content/plugins/super-forms/uploads/php/files/3a9609d13bbb93087dbd3a0c12b751cc/zoned.pdfIn PDF document text
    • http://mhfmjournal.com/data/22/2/55/64/2544879/user/2788947/htdocs/userfiles/file/sojivoxuxide.pdfIn PDF document text
    • https://admonks.ru/wp-content/plugins/super-forms/uploads/php/files/0440091cdfe394642511d41f2433aa29/kuwoguri.pdfIn PDF document text
    • https://bladmedyczny24.pl/wp-content/plugins/super-forms/uploads/php/files/ce21f2872ee26195ee4163bd2f3724d1/jitene.pdfIn PDF document text
    • http://dh-cell.com/ckfinder/userfiles/files/latuzalimomesozogorefowe.pdfIn PDF document text
    • http://waypl.pl/upload/File/43401237035.pdfIn PDF document text
    • http://robwalker.net/fckupload/file/bugejasubuw.pdfIn PDF document text
    • https://www.penyembuhanholistikreiki.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608a6622352d1---6171983523.pdfIn PDF document text
    • https://alphaveneers.co.uk/wp-content/plugins/super-forms/uploads/php/files/3bc9fc11c82fc3107843057ef15f02e4/jabejexekog.pdfIn PDF document text
    • http://erkerlaender.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607af9c91c3db---55240405786.pdfIn PDF document text
    • http://eca.or.th/ckfinder/userfiles/files/jakumowiroxot.pdfIn PDF document text
    • http://eastwoodfamily.net/userimages/9786510846.pdfIn PDF document text
    • http://maryalo.com/userData/board/file/8184235339.pdfIn PDF document text
    • http://www.kickcommerce.com/userfiles/file/dagekigew.pdfIn PDF document text
    • https://husvagnsexpo.se/wp-content/plugins/formcraft/file-upload/server/content/files/1609b3961e0e7b---fomulepegizale.pdfIn PDF document text
    • https://www.gasserbush.com/wp-content/plugins/super-forms/uploads/php/files/25022048ddc1576c5247e77ced751915/xekuxizopusananuvu.pdfIn PDF document text
    • http://getvisa.ru/images/File/66211322729.pdfIn PDF document text
    • https://fitnessrev.net/wp-content/plugins/super-forms/uploads/php/files/75quumhuc4nv76uj00upbi8u04/sevujizevaseg.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=the+great+gatsby+chapter+5+discussion+questionsPDF 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_off0000d227.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD227 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ea3e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA3E 11344 bytes
SHA-256: ba463114ab7eab89bdf919d913410f644f89351db443ccd2487d3f6c5eaeadc9
font_02_sfnt_off00010442.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10442 17960 bytes
SHA-256: 0bf2636c124560605d93c4a08025ab84da1deccfa6ca23730a24c2323e6a1287