Malicious PDF — malware analysis report

Static analysis result for SHA-256 663a0aa6a8c829f9…

MALICIOUS

PDF

85.7 KB Created: 2021-08-24 23:00:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: cea37aa6e12e837bc97921de7a3a6ff7 SHA-1: 55fe7a5ab3a7484e65ea4d90d1d6dc5deaf34af6 SHA-256: 663a0aa6a8c829f978d896a6b6824d98dea8d9a124e13c4e208ffeb6924f0a07
156 Risk Score

Malware Insights

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

This PDF was flagged by a machine learning classifier and ClamAV as malicious, indicating it likely exploits a vulnerability or contains malicious content. The heuristics reveal it functions as a link farm, directing users to multiple external URLs hosted on compromised CMS uploads and disposable domains, suggesting a phishing or malware distribution attempt. No scripts were extracted, but the PDF structure and URL patterns are indicative of a malicious payload delivery mechanism.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

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://maketmaster.ru/admin/ckfinder/userfiles/files/56330811682.pdf
    • https://eduinfinite.com/wp-content/plugins/super-forms/uploads/php/files/b475d70e6c6e523d175bb0ab2bbb8f6f/64496860778.pdf
    • https://homeaestheticsllc.com/wp-content/plugins/super-forms/uploads/php/files/86783a8e948178c074b1041aa7f743b1/zovatutigijure.pdf
    • http://www.agenbenangbandung.net/file/3705516097.pdf
    • http://www.rebranded.tv/wp-content/plugins/formcraft/file-upload/server/content/files/160a9f5409de8e---mujululugejavivonadezudu.pdf
    • https://estigotours.com/wp-content/plugins/super-forms/uploads/php/files/7daa8614d48126fa35b629c5cc9b3013/kuxux.pdf
    • http://2015.letnifestiwal.pl/ckfinder/userfiles/files/84467600383.pdf
    • https://weeb.nu/userfiles/file/34247897777.pdf
    • http://www.korayozelguvenlik.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087a0b6677ef---majitikotakexag.pdf
    • https://emotionalgift.com/ckfinder/userfiles/files/82176304367.pdf
    • https://partnyor.az/userfiles/file/lexazebajexekusinomag.pdf
    • https://wpsqld.com.au/wp-content/plugins/super-forms/uploads/php/files/df05776e804471051028f5aa9324fca1/kiwumelusopinuribekasogi.pdf
    • https://daaeportrett.no/upload/file/fejepevatisufimime.pdf
    • http://dienmaythanglong.org/uploads/files/jafunum.pdf
    • http://bruisedreedfoundation.org/clients/4/4d/4d9d7eec3bf3a09fa0457ace138f6a4e/File/napawuzutixujadul.pdf
    • http://www.dadosefatos.net.br/wp-content/plugins/formcraft/file-upload/server/content/files/16076a3e37af54---nabiwizata.pdf
    • https://www.lumisolar.pe/wp-content/plugins/formcraft/file-upload/server/content/files/1607ef98bc3a5f---1622286452.pdf
    • https://blagoustroystvo24.ru/ckfinder/userfiles/files/48242404491.pdf
    • http://nnrhc.com/clients/9/98/980d61ede38c9a35fe3396fb65651545/File/mosake.pdf
    • http://vhktn.at/images/content/files/36313471514.pdf
    • http://winfielddeli.com/ckfinder/userfiles/files/83237390864.pdf
    • http://schodylux.pl/userfiles/file/letorotalukitid.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=invading+personal+space+meaning
    • 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_off0000e5ba.bin
668e575d1f8c796d93147271e1dffe53ddf740dd935b1ecd65d8440498696cea
pdf-font-stream PDF embedded font (sfnt) at offset 0xE5BA 10776 bytes
font_01_sfnt_off0000fe41.bin
830b409c59d82534428fff4b1a7eee15c4bb5e8481b298648f2ad49488332a92
pdf-font-stream PDF embedded font (sfnt) at offset 0xFE41 19912 bytes
font_02_sfnt_off00013092.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13092 16792 bytes