Malicious PDF — malware analysis report

Static analysis result for SHA-256 5789939dc39b4988…

MALICIOUS

PDF

83.1 KB Created: 2021-07-01 09:46:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 5b12c37567dd3ee95ffe8e1813a62ec7 SHA-1: f1497ab151a6bd87250b20af2b488660604c9779 SHA-256: 5789939dc39b498839c6de7882a153120bc504bccae5f8509d785f2dcec53a93
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous embedded URLs, many pointing to compromised CMS upload directories, suggesting a link farm designed to redirect users to malicious content. The presence of external URI heuristics and the overall structure point towards a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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 https://allytemp.ru/uplcv?utm_term=report+writing+ppt
    • http://www.luminicaambiental.com/wp-content/plugins/formcraft/file-upload/server/content/files/160739d9f4a277---95598862719.pdf
    • https://bamor.org/userfiles/file/rulukipojoris.pdf
    • http://phenix-security.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1609d94e24a6c2---54665983933.pdf
    • http://happinessgown.com/upload/users/files/87327101189.pdf
    • https://www.cpro.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160781897b96c5---vosalijivorot.pdf
    • http://www.caslyn.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160cedc718e290---94976763668.pdf
    • https://finestblogger.de/wp-content/plugins/super-forms/uploads/php/files/q087201sifh6frirbra13rglmu/82390562668.pdf
    • https://enville.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c77275135d1---88918031463.pdf
    • https://www.kiteschule-kiel.de/wp-content/plugins/formcraft/file-upload/server/content/files/160aa92ae5be05---93251769269.pdf
    • https://www.sahabatkeluargahomecare.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070665ae72e6---pijumageka.pdf
    • http://vitanova-cattery.com/upload/file/ritoxotafuka.pdf
    • https://anmimar.com/royal/userfiles/file/woviwidonosenonax.pdf
    • https://kicksomeglass.com/wp-content/plugins/super-forms/uploads/php/files/bd157c9dcea003988e8d7234ba17ae7b/gobefijunizikawufu.pdf
    • http://aldo-ins.com/userfiles/file/lusijebevolebelo.pdf
    • https://www.webplease.it/wp-content/plugins/super-forms/uploads/php/files/62usa1a86nbu0jjkfkjj3gmro4/rixujewuvodisemobu.pdf
    • http://aroma-es.site/yamituki-n/uploads/files/dujoxabufawenoda.pdf
    • https://www.budgetskemaet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/1607ed036841a4---nijalakedatejowerigi.pdf
    • https://roadtoring.com/wp-content/plugins/super-forms/uploads/php/files/9927948375a6a0645f4c65fc68a3c02e/wujizobubujajolowevosovut.pdf
    • http://qboardapp.com/wp-content/plugins/super-forms/uploads/php/files/f7fd31b32cb679bf45ed4811f2b6fbfa/12019181524.pdf
    • https://gemwares.com/userfiles/file/82690595736.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_off0000e607.bin
f35bdd858bb68134a9780b273b4f7bbd67a8867fd4e50c5e4cf51c84c274135f
pdf-font-stream PDF embedded font (sfnt) at offset 0xE607 10184 bytes
font_01_sfnt_off0000fcff.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFCFF 16792 bytes
font_02_sfnt_off00011511.bin
c2e56b0df4d653ed3c3a3812653e6d2bf2ebdf17d3d1c4e759b98aec7dde71d7
pdf-font-stream PDF embedded font (sfnt) at offset 0x11511 16512 bytes