Malicious PDF — malware analysis report

Static analysis result for SHA-256 6b1f9c7ce2bcff39…

MALICIOUS

PDF

84.3 KB Created: 2021-07-02 09:15:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: a8a08a41fed13e1301ca8a0831fa05df SHA-1: a6a0376ceacea222deac890158be4df7890745d7 SHA-256: 6b1f9c7ce2bcff39b90b545773957963a80a0c1f19c46c4ad2b1ccfa2a387006
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics as malicious, including a critical ClamAV detection and an ML classifier indicating a high probability of maliciousness. It functions as a link farm, containing numerous URLs pointing to compromised CMS uploads and disposable hosting, suggesting an attempt to redirect users to phishing sites or download further malware. The presence of external URIs and the overall structure indicate a likely spearphishing attachment used to deliver malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://aarhuskortet.dk/images/file/13252279791.pdf
    • https://cal.lighting/wp-content/plugins/super-forms/uploads/php/files/faf61bb7254fdab4428f94de8134b73e/xutopawovibesekaxa.pdf
    • http://marcobernini.it/userfiles/files/81746095047.pdf
    • http://makaifruits.com/wp-content/plugins/formcraft/file-upload/server/content/files/16092096a54c9f---63668222614.pdf
    • http://popnmusic.fr/userfiles/file/wojinaken.pdf
    • http://novaserv.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f0d2cd174a---mumelutupu.pdf
    • http://altaprecision.com/userfiles/file/41009610499.pdf
    • http://weclassof86.com/clients/6/6d/6dc59c75684a9be5e3a4726337e2fa3a/File/75496263147.pdf
    • http://maidnheaven.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a19a168e4a9---12653675607.pdf
    • http://growlink.biz/userfiles/file/vozurupivuwasixowufigo.pdf
    • http://bitite.lv/media/txt/122/file/dusupizawata.pdf
    • https://www.ideaklinikbakirkoy.com/wp-content/plugins/formcraft/file-upload/server/content/files/16081d9bc75da8---33197047189.pdf
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1607e1cd229246---12822295143.pdf
    • http://montaze.org/democms/userfiles/file/durigibirosopeza.pdf
    • http://www.ashtralmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/160879db4861ea---44717617029.pdf
    • http://www.marcado.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160a0b18bb9338---26724036096.pdf
    • http://triumphtoday.org/wp-content/plugins/formcraft/file-upload/server/content/files/1608f1886b85c8---83354013297.pdf
    • https://amesmedicalservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e6d2e612f1---44015311696.pdf
    • http://evabody.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16088bf46cd186---jalapiliromogutedafili.pdf
    • https://alenakovalchuk.ru/wp-content/plugins/super-forms/uploads/php/files/9c0d8c1ca1afdfc55e8502510e28a4e1/vesipekebibakupetulu.pdf
    • http://sportschoolindex.nl/images/uploads/41630495731.pdf
    • https://kme.pl/global/app/webroot/uploads/file/16234299422446.pdf
    • https://arredamentigiacobbe.it/file/30857117109.pdf
    • https://menu2uplus.com/images/file/rinaladureguvedujerivagut.pdf
    • http://iphysiology.ru/upload/pifotodufisebisumova.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=ism+information+systems+management
    • 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_off0000e952.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE952 16792 bytes
font_01_sfnt_off00010169.bin
9f0130032245c72a695d09ef6394d2f51a48e95df2b26752fdd95cb36f38ee4e
pdf-font-stream PDF embedded font (sfnt) at offset 0x10169 10576 bytes
font_02_sfnt_off00011990.bin
31949c82183ec5ed213029c5817006d4168c151245c0e6d757334e3eb02a9429
pdf-font-stream PDF embedded font (sfnt) at offset 0x11990 16360 bytes