Malicious PDF — malware analysis report

Static analysis result for SHA-256 c5cf4f7c956f2613…

MALICIOUS

PDF

122.2 KB Created: 2021-08-11 00:26:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: b89a843c88510378f2419cc9cc9d94cc SHA-1: ea4b972e15913855c3091c64cc3f7535690e0488 SHA-256: c5cf4f7c956f2613e13a065294cd08059449f71ff3604f598810a2f7a635eada
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous links, many pointing to compromised WordPress sites hosting other PDFs. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The structure suggests a link farm designed to obscure the ultimate destination and evade basic detection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://www.heainc.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bb2518a4e46---8660816584.pdf In PDF document text
    • http://www.majorisinvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160ae2c6952b7a---fugidazonozevo.pdfIn PDF document text
    • http://axwelindia.com/uploads/74149358567.pdfIn PDF document text
    • http://jucal.es/images/file/pufaduxajadefa.pdfIn PDF document text
    • https://www.pennlighting.com/wp-content/plugins/super-forms/uploads/php/files/fb411a04a41f8690609ad73b0d0fd5a6/jeturufor.pdfIn PDF document text
    • http://afgventuregroup.com/cfiles/file/jisoso.pdfIn PDF document text
    • https://www.techsrollout.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a986974bf88---33803430075.pdfIn PDF document text
    • http://allegroescrow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160af95a1e0fc2---xasopogenan.pdfIn PDF document text
    • https://www.helpforbusymums.com/wp-content/plugins/super-forms/uploads/php/files/2f3c85c024301977ea75f38e073eacf2/nevudurizobidobe.pdfIn PDF document text
    • https://cavalier-hundezucht.ch/userfiles/file/kunasif.pdfIn PDF document text
    • http://wasserburg.pl/userfiles/file/1778250846.pdfIn PDF document text
    • http://kursadowicz.pl/Upload/file/87631097543.pdfIn PDF document text
    • http://ipjanah.ir/wp-content/plugins/super-forms/uploads/php/files/919o8kbqrpjv877krl4vdh38g2/95803567990.pdfIn PDF document text
    • http://rapabzenec.cz/obrazky/files/87052176614.pdfIn PDF document text
    • http://steelbo.com/uploads/admins/u0/files/20210622175009.pdfIn PDF document text
    • http://ajtoablakcentrum.com/_user/file/61960773045.pdfIn PDF document text
    • http://asijskepotraviny.cz/files/file/wisaxobajobinotipexarup.pdfIn PDF document text
    • https://floorco.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/32b03a889dd0c63955e1f3e627df0f24/29808840903.pdfIn PDF document text
    • https://mimpishio1bet.net/contents//files/wavakikagojogalifevok.pdfIn PDF document text
    • http://www.ecostroyservis.ru/File/sajatew.pdfIn PDF document text
    • http://endustriyelkiralama.com/wp-content/plugins/super-forms/uploads/php/files/tcucvfpsm1kvht43t4pddl6oc9/devafulajularixodonedipo.pdfIn PDF document text
    • http://www.louthadventures.ie/wp-content/plugins/formcraft/file-upload/server/content/files/1607e1fedafcca---somaladopumogojenanuvenup.pdfIn PDF document text
    • http://vincityhomes.vn/wp-content/plugins/super-forms/uploads/php/files/duspb0g1n7st7l95p2s4e20gv7/firevad.pdfIn PDF document text
    • https://solarconsulting.org/wp-content/plugins/super-forms/uploads/php/files/fdc9b884e0573f67c753cf7dae034894/72394165922.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=what+is+eccentric+loading+exercisePDF 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_off0001792b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1792B 18388 bytes
SHA-256: b364d625fc16684312465a73bb24ea05fab1484bfa8b5c12b1bdbfd3a0afabc7
font_01_sfnt_off0001a93d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1A93D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001c154.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1C154 10744 bytes
SHA-256: df5d60a8d56f23ff06de47ab6d7619d7a5de9a121d9e1b6e68b0aa5a5b0b4ffd