Malicious PDF — malware analysis report

Static analysis result for SHA-256 fc336c6269b9812e…

MALICIOUS

PDF

78.6 KB Created: 2021-09-01 05:24:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: dfaaa61f4d5b5202953c8a04cd62e1f0 SHA-1: 3da6b8f8f348ef9836b7c9814f22ebb14d27b66e SHA-256: fc336c6269b9812ecf39ba6685386a4e6c4889e19f04308ba9da8f28e8e9bd29
204 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript and numerous links, many pointing to compromised WordPress sites or disposable hosting, suggesting an attempt to distribute malicious content or phish users. The ClamAV detection and ML classifier strongly indicate malicious intent, likely involving the exploitation of PDF vulnerabilities to execute code or redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

Heuristics 8

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://krisoc.ru/uplcv?utm_term=overweight+two+year+old
    • http://allegroescrow.com/wp-content/plugins/formcraft/file-upload/server/content/files/16081cfe47c982---51699538068.pdf
    • http://costruzionibulagna.it/userfiles/files/xaderixubokifenuwig.pdf
    • https://betonwerkendejonge.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160b5523828225---sasukuvaluloxumifida.pdf
    • http://www.oschouston.com/osc/wp-content/plugins/formcraft/file-upload/server/content/files/160a322475ae39---37142569006.pdf
    • http://vtvxm.vn/userfiles/file/67054954030.pdf
    • http://michelesherrinlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/nerab.pdf
    • http://kayapaliinsaat.net/file/7956878256.pdf
    • https://krzczonowice.pl/gfx/file/pekidemamatufevu.pdf
    • http://ambulatorioveterinariobubiniregini.eu/userfiles/files/98191588323.pdf
    • https://beaufortbond.com/wp-content/plugins/super-forms/uploads/php/files/480f394fc2e98f1075fb2da9cf48b66b/paluwawow.pdf
    • https://xenang-mitsubishi.com/fckupload/file/dufibufixixiwitasumen.pdf
    • http://maezawa-jidousha.com/js/upload/files/turinubezuruvokewapotuj.pdf
    • http://hzbmsj.com/images/upload/File/nazovemunarutekumanukokeg.pdf
    • https://www.caesarstravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16083113edf1d6---70228291938.pdf
    • http://ecandrychow.pl/Image/files/xemasinokixumobo.pdf
    • https://www.lindopoint.it/wp-content/plugins/super-forms/uploads/php/files/6942bb65f37c902cd63e94ab4da2de8c/palapazikutanusomabizusov.pdf
    • https://wecareprogram.org/images/file/74990652007.pdf
    • http://okulsanmalatya.com/imgup/file/3122635191.pdf
    • http://paintingservicesonline.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160abc80586af4---kudujuxuzekiposewodaka.pdf
    • https://amezdigital.com/wp-content/plugins/super-forms/uploads/php/files/d040921c340a1f13a1372ff28c88eae0/sigafasotija.pdf
    • http://lhsclassof1971.com/clients/74120/File/wulate.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
stream_007_off00011430.bin
eb30da2ad0f7081939e8a5692bb41c639be196892a9f52c82ad721381fe82c44
decompressed-pdf-stream PDF FlateDecoded stream at offset 0x11430 10548 bytes
font_00_sfnt_off0000ce63.bin
b2c5ae3ceed71ffe41d1509fc326d123087b8dbd0a8356e1310a3bcba9aacd83
pdf-font-stream PDF embedded font (sfnt) at offset 0xCE63 17664 bytes
font_01_sfnt_off0000fc19.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFC19 16792 bytes