Malicious PDF — malware analysis report

Static analysis result for SHA-256 c958a1c25a679de5…

MALICIOUS

PDF

82.1 KB Created: 2021-09-06 16:03:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 15417e99539d552d7e1f2bf855e1a2b6 SHA-1: 2d814266ecf7ea4b368950afc67972cbd864ca76 SHA-256: c958a1c25a679de53307758740b3f86f76a1532c41eb5f666d7e1f2079328503
156 Risk Score

Malware Insights

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

This PDF file was identified as malicious by a ClamAV detection and an ML classifier. It functions as a link farm, containing numerous URLs that point to compromised WordPress upload storage and other disposable hosting sites. The primary purpose appears to be directing users to these external resources, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

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://sckstone.com/wp-content/plugins/super-forms/uploads/php/files/48c279e5ba7a5efde4202bbb2cb558df/20185992397.pdf
    • https://agmatbaa.com/upload/files/jarinenesa.pdf
    • http://yamamatoen-wanwan.jp/ckfinder/userfiles/files/23932658216.pdf
    • http://apvn.info/userfiles/file/bolimabolip.pdf
    • http://barbusci.it/maisUserFile/file/teralanezafagaduzoxukowe.pdf
    • http://sunnysidehigh65.com/clients/d/d0/d00d1ad1640c45b888f5e58ac216a5d1/File/96155978964.pdf
    • http://bilagroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c0d63f769e4---39965187030.pdf
    • http://kfbi.ru/content/file/9027217141.pdf
    • https://viajespereira.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608d6a67ad516---texomi.pdf
    • https://aslimitada.com/userfiles/file/pekomitig.pdf
    • http://at2apigroup3.com/contents/files/63940509317.pdf
    • https://childprotectionindia.com/lexcyberia/userfiles/files/73377054886.pdf
    • http://amon-syotengai.com/userfiles/file/33583232779.pdf
    • http://www.gametimecatering.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075fad8e05b9---58973811088.pdf
    • http://rajskiewakacje.pl/userfiles/file/62546140317.pdf
    • http://changwontour.kr/FileData/ckfinder/files/20210625_169327503A41BD54.pdf
    • http://bluecars.pl/userfiles/file/dezevibedatonadenekov.pdf
    • https://phoenixknights.co.uk/wp-content/plugins/super-forms/uploads/php/files/f4bc3727781a4ab9a8cc060fa640b963/wizobetameli.pdf
    • http://www.dj-csnl.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160d3604937dcc---lozogadilupogor.pdf
    • http://amtusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c0a2502b8f1---22846393849.pdf
    • http://kolkandkolkdesign.com/site/data/ws/files/61621734744.pdf
    • http://asustainable.com/global/file/xabev.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=el+materialismo+histerico+xavier+velasco+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_off0000d9a7.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD9A7 16792 bytes
font_01_sfnt_off0000f1be.bin
b577cf4d11e8be60597cb07652ce9c3198a01d0b72dc64326ee55f93056ffc83
pdf-font-stream PDF embedded font (sfnt) at offset 0xF1BE 10932 bytes
font_02_sfnt_off00010b16.bin
a8dfcaea5fa5b3f064bba326f96ee68738e6bd9d36b271a8cf586142e01a39fe
pdf-font-stream PDF embedded font (sfnt) at offset 0x10B16 18924 bytes