Malicious PDF — malware analysis report

Static analysis result for SHA-256 a5c2a7b91a871f1d…

MALICIOUS

PDF

88.1 KB Created: 2021-09-02 16:48:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: fbbbcf21630cf433fa8ade3293cfea29 SHA-1: cab71ef346de8f6199250d429f155be7a72ab2db SHA-256: a5c2a7b91a871f1d2e44865f70a7f5db2789e53ba30164c5f2286cddc4ba361e
156 Risk Score

Malware Insights

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

This PDF file was flagged as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to multiple compromised or disposable hosting sites, likely for phishing or malware distribution. The presence of numerous embedded URLs, many pointing to suspicious domains, supports this conclusion.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9966

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 http://longvu.vn/Images_upload/files/87156946944.pdf
    • https://fortlauderdale-carservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1610af5e2d0dfd---97548916908.pdf
    • http://meteosputnik.ru/userfiles/file/gawepevuferevila.pdf
    • https://bulgariapools.com/contents/files/53877508524.pdf
    • http://seanbittinger.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/81828280397.pdf
    • http://uniqueaddress.in/crm/files/detik.pdf
    • https://segurosjdd.com/wp-content/plugins/super-forms/uploads/php/files/bl08obqfccdigtg7c12japuqe6/muveved.pdf
    • https://www.myjamaicais.com/wp-content/plugins/super-forms/uploads/php/files/0887a38e50dc2cac688a3b29d286c6ae/wubuvaxejikawerazoni.pdf
    • https://eyestech.in/wp-content/plugins/super-forms/uploads/php/files/s24uvkdutu85gvso7rihst273f/rovon.pdf
    • https://gccpay.net/wp-content/plugins/super-forms/uploads/php/files/c592a8e008a63ddb0e8c3f3bee48d7bc/nogusamobeputu.pdf
    • http://zawodydrwali.pl/app/webroot/userfiles/file/namujiwemumemisubor.pdf
    • http://branpc.in/ckfinder/userfiles/files/32410598620.pdf
    • http://clairerolo.com/userfiles/file/xipujajazaxowunasup.pdf
    • https://emprenderem.cl/files/32608800812.pdf
    • http://duszek-lasu.pl/userfiles/file/kiwosodus.pdf
    • http://chaitraglaze.com/uploads/libufuni.pdf
    • http://arlingtonhigh1960.com/clients/881088/File/49486967149.pdf
    • https://lakecountyoralsurgery.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b23f7d06d5a---62001998205.pdf
    • https://pinotcar.com/wp-content/plugins/super-forms/uploads/php/files/0adcb88ea698f13f722eb320d89e390e/gigixetomow.pdf
    • http://reiki-roots.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160aafacc1e4b3---vewubokipazeperatew.pdf
    • https://kfk-dekoration.dk/images/uploadedimages/file/39091705931.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=introduction+to+drone+technology+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_off0000f601.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF601 16792 bytes
font_01_sfnt_off00010e18.bin
18cdd745be275ae3980e4c4e146e5531a85374f08aca240deecf245d032d9e8e
pdf-font-stream PDF embedded font (sfnt) at offset 0x10E18 10736 bytes
font_02_sfnt_off00012675.bin
c71ed7aad210b0e17efedf465006ddbbac1dfc9b22af13aa3e1c4cd4c39ddfb3
pdf-font-stream PDF embedded font (sfnt) at offset 0x12675 17212 bytes