Malicious PDF — malware analysis report

Static analysis result for SHA-256 f5e27f2e5fd3d1f8…

MALICIOUS

PDF

71.5 KB Created: 2021-07-02 01:13:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 0191b64e7a8ccea3e6bbe24acc4abd68 SHA-1: aad67993a7b82ab279c1991a819759aaa4200e45 SHA-256: f5e27f2e5fd3d1f85ca346b5de7fdb19153ce1f7094b7c216e4a31dac56c9275
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Numerous heuristics identified the PDF as a link farm, with many links pointing to compromised WordPress upload directories and disposable hosting. The embedded URLs suggest the document is intended to redirect users to external sites, likely for phishing or to download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9971

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://oniceh.ru/uplcv?utm_term=constitution+book+answers
    • http://mognational.com/wp-content/plugins/formcraft/file-upload/server/content/files/160799b5cc29ba---20086675718.pdf
    • http://casier-a-bouteilles.com/file/makofazitodower.pdf
    • http://luingpyrex.cz/foto/Image/file/780488042.pdf
    • http://www.webtony.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b039b7e5e5f---menijemamesajuzuj.pdf
    • https://reifenscho.de/wp-content/plugins/formcraft/file-upload/server/content/files/16073aac8ed5d3---nezuxudubetuv.pdf
    • http://www.radioemka.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d482f2c35f---wezekebasajefu.pdf
    • http://thrifty-uy.com/files/others/zugopinogazi.pdf
    • http://osullivanspressurewashing.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608772e6d050e---bizozukexuxetosexibaj.pdf
    • http://msci.com.ng/wp-content/plugins/formcraft/file-upload/server/content/files/160db2a1781c22---76297255223.pdf
    • http://hhs63.org/clients/8/88/88ec95b665b56da82b1de85f097fba10/File/71330185310.pdf
    • http://asdgolfclubtoscana.com/writable/public/userfiles/file/luvedujumajatekidu.pdf
    • http://www.hkwebdesign.com.hk/wp-content/plugins/formcraft/file-upload/server/content/files/160c3543127a88---gimafosevogobutifozi.pdf
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/895e0e5da34bb4ded0244f43b170684f/fiwodanilawerutori.pdf
    • https://www.a2zmedical.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160809e5142265---xedux.pdf
    • http://sunnysideclassof64.com/clients/a/ac/acc4ccb49d7935ca36198347b895393e/File/nonutunuwozudivofe.pdf
    • http://xn--pr3b03lcdvwu9dpynqkc.com/DATA/file/20210619174129.pdf
    • http://iehyun.com/editorupload/file/rezila.pdf
    • http://duancanhotot.com/upload/files/vusekoz.pdf
    • http://papianiarch.it/userfiles/files/81830340380.pdf
    • http://botanicgardenscafe.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160a882f58bc7b---29204492462.pdf
    • http://goldnumber.info/userfiles/file/97589220883.pdf
    • https://www.chartsunlimited.com.ph/wp-content/plugins/formcraft/file-upload/server/content/files/1607df5e7b4125---zosepiga.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_off0000b8e6.bin
44256712dcef39eb2fdd896beb7dc89370ec0816989c5aea1876185e502ee30b
pdf-font-stream PDF embedded font (sfnt) at offset 0xB8E6 14988 bytes
font_01_sfnt_off0000df0b.bin
cf8e89d6dfc29694bf78884821b13647e2a01cc6c0251feb89d6dd2c6227ef64
pdf-font-stream PDF embedded font (sfnt) at offset 0xDF0B 10504 bytes
font_02_sfnt_off0000f739.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF739 16792 bytes