Malicious PDF — malware analysis report

Static analysis result for SHA-256 55f89d2f2a97d0b2…

MALICIOUS

PDF

94.2 KB Created: 2021-09-16 19:33:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 710046414b3fd6bd1fee3c165cdb13bf SHA-1: 59c637d531c6077a8c33951d7eec64c3552484a2 SHA-256: 55f89d2f2a97d0b2e30b58d09f90195b787239214cb1ea36e2cad81f1863be63
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by multiple heuristics, including a critical ClamAV detection and an ML classifier indicating maliciousness. It contains numerous external links, many pointing to compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users. The presence of embedded URLs and the nature of the heuristics strongly indicate a phishing or malware distribution attempt, likely initiated via spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9897

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://wastran.ru/uplcv?utm_term=androidx+navigation+drawer
    • https://bf-pomosch.ru/wp-content/plugins/super-forms/uploads/php/files/ptubv1b4pculid8gnaq8ijtul7/26121966256.pdf
    • http://budoprojekt.eu/obrazy/file/wupafokox.pdf
    • http://royal-pizza.eu/files/file/22918950501.pdf
    • http://yilbasipromosyonu.com/userfiles/file/32864739741.pdf
    • https://yuktiedu.com/wp-content/plugins/super-forms/uploads/php/files/3a73944b4b5af1c11c0c5ee2d11ca406/kekejurolotugujuxa.pdf
    • http://kajo-frings.de/userfiles/file/9629607183.pdf
    • http://orthopediedelft.eu/files/59610233197.pdf
    • https://tuinvandecruys.be/file/janibegezubadanokalazopuv.pdf
    • http://tdsns.ru/userfiles/file/pepigunovofeme.pdf
    • https://www.le-domaine-de-hauterive.fr/ckfinder/userfiles/files/93056620984.pdf
    • http://millecolori.it/images/file/97066814040.pdf
    • http://dglytbt.com/upfolder/e/files/20210908183624.pdf
    • http://hqshop24.com/userfiles/file/zizevokinogakat.pdf
    • https://takipcisec.com/calisma2/files/uploads/60087242092.pdf
    • http://art-wonders.com/ckeditor/ckfinder/core/connector/php/uploads/files/sasiri.pdf
    • http://galluccifaibano.com/userfiles/file/26118410.pdf
    • https://binhruamuinanobac.com/wp-content/plugins/super-forms/uploads/php/files/hp4h8fs1d4o5v0mbi8ktijod5i/mebuzitifojipowuvawe.pdf
    • http://alemotta.com/resources/original/file/1031015162.pdf
    • http://winfielddeli.com/ckfinder/userfiles/files/xemubotolexorepiga.pdf
    • http://smartraoptics.com/fck_filemanager_upload/file/rulajoritutetozivemitudul.pdf
    • http://fskyok.com/uploadfile/files/porametudizufafububat.pdf
    • https://dijitalsanat.link/upload/files/xasexokexotorugowomuka.pdf
    • http://lisahyatthealth.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136cd8c539a3---30611728047.pdf
    • http://allier.proximeo.com/ckfinder/userfiles/files/miverelivesiv.pdf
    • http://food-cloud.com/home/food-cloud/www/site/site/data/files/43642678429.pdf
    • http://test-immo.com/file/17868655039.pdf
    • https://stollerco.com/testingsites/advantage_aviation/assets/media/file/fujosolizijonufoxijupibip.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00010cd8.bin
9f57087db2a59986db9ca7d0b335f92843366be21005ba7b3e3c2e14332c95af
pdf-font-stream PDF embedded font (sfnt) at offset 0x10CD8 18080 bytes
font_01_sfnt_off00013b48.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13B48 16792 bytes
font_02_sfnt_off0001535f.bin
32b8f67070aebf3135ce22ce8c5082874f708e6c404f879becce7b26c191b8ec
pdf-font-stream PDF embedded font (sfnt) at offset 0x1535F 10444 bytes