Malicious PDF — malware analysis report

Static analysis result for SHA-256 5a7d923123e661e0…

MALICIOUS

PDF

98.5 KB Created: 2021-07-05 00:00:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: b101120e9c076973a12ebc663fb98665 SHA-1: 02b2ba94643d0dca1b13fcc3fd8a3f7321dbb149 SHA-256: 5a7d923123e661e059c81411cbfb3500dbe13b0d806e896a1e367d6da82fe597
156 Risk Score

Malware Insights

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

The PDF document contains numerous links pointing to compromised WordPress sites and other domains, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or distributing further malware. The document body is heavily obfuscated and unreadable, providing no direct content clues, but the heuristic firings clearly indicate a malicious link distribution pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9898

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://garglob.ru/uplcv?utm_term=thoracic+outlet+syndrome+amboss
    • https://militarynetwork.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1608c8bd3ab002---31162913517.pdf
    • http://vudafrique.com/wp-content/plugins/super-forms/uploads/php/files/e99e68fdd3401989e9657cd353613938/tifijivutup.pdf
    • https://www.pfgpartners.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16076c33e6d7fe---bapudaritewera.pdf
    • http://hopkinshigh1988.com/clients/75739/File/bamafalubago.pdf
    • http://chickendaylacrescenta.com/uploads/files/83324842918.pdf
    • https://atlanthealth.com/wp-content/plugins/super-forms/uploads/php/files/00416d98c94146660361bd27a4314d7b/fafutenepamuruzo.pdf
    • http://harchovyk.com/userfiles/file/zavuj.pdf
    • http://bpsstudio.hu/uploads/47923396551.pdf
    • http://foire-fromages-et-vins.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609786f56221f---rufibopa.pdf
    • http://prociweb.hu/sites/files/file/lixepubopi.pdf
    • http://lso-msm.fr/userfiles/file/xinipamewafobonagorewu.pdf
    • https://www.advids.co/wp-content/plugins/formcraft/file-upload/server/content/files/160b8a4733dd29---nukofijolulafenixuwe.pdf
    • https://www.baptistenhardenberg.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1606cc22c1e9d1---sisuxujavagiked.pdf
    • https://www.sharpeningfactory.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a3b94c45bcf---lipekikufisarunubojot.pdf
    • https://laneopx.com/wp-content/plugins/formcraft/file-upload/server/content/files/160809f0e5ffeb---xuxezakuzapolevalire.pdf
    • https://bluetact.com/locktactyuma/userfiles/file/1646497024.pdf
    • http://mclarenquartz.in/ci/userfiles/files/88853500010.pdf
    • http://prvugkh.ru/uploads/files/zevunalol.pdf
    • http://www.miamiairportlimo.net/wp-content/plugins/formcraft/file-upload/server/content/files/160b4d4da9f7e1---94339574104.pdf
    • http://timandlor.com/userfiles/file/taxepovibaxusekalinula.pdf
    • http://eatatrudy.com/uploads/files/78766016759.pdf
    • http://gorisum.net/fckeditor/upload_file/file/xusulo.pdf
    • https://advicezone.org.uk/wp-content/plugins/super-forms/uploads/php/files/bfjvgmb0jd19v4e53mboebr8cd/16761097498.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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00010bd1.bin
150d99dabe09e1376b7d083ac54f697b773f5202a16ec0e01da69a5487201440
pdf-font-stream PDF embedded font (sfnt) at offset 0x10BD1 3924 bytes
font_01_sfnt_off00011b56.bin
a4c741c8a1c41c1bd3de05e2a4267b71cb1572a825d4b51bc49ff9431652b0c3
pdf-font-stream PDF embedded font (sfnt) at offset 0x11B56 10952 bytes
font_02_sfnt_off0001348c.bin
35b44bdc40c62f4cd069bd1fb8f15f6f6a5c6548002fe6adce620969e2735d5c
pdf-font-stream PDF embedded font (sfnt) at offset 0x1348C 17760 bytes
font_03_sfnt_off00016296.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x16296 16792 bytes