Malicious PDF — malware analysis report

Static analysis result for SHA-256 4c832762d5c31347…

MALICIOUS

PDF

82.9 KB Created: 2021-07-02 09:49:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 767485bcd2857eba82a9a26e27bc7e96 SHA-1: 0ad3e7b5207ca95b07959eea37cf301686b6bc24 SHA-256: 4c832762d5c313478250bc16bb4610296851d3297d4f7cdb4fdc035958ad6799
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics as malicious, including a critical ClamAV detection and an ML classifier indicating a high probability of maliciousness. It contains numerous links pointing to compromised WordPress upload directories and disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of these links indicates an attempt to lure users to external sites, likely for phishing or to download further malicious payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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://infrive.ru/uplcv?utm_term=physical+and+chemical+structure+of+chromosome+pdf
    • https://sidexsideaudio.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609691f717ccf---walew.pdf
    • http://dolphinegypt.net/userfiles/file/sobakowuvozedutif.pdf
    • http://1utilaje.ro/mm/file/82363871840.pdf
    • https://sckstone.com/wp-content/plugins/super-forms/uploads/php/files/1944a6dae31168bbf2f8c9b651291cb8/busikedazibuwalakixi.pdf
    • http://ozdoby-betonowe21.pl/Upload/file/73332602024.pdf
    • http://www.driftime.ee/wp-content/plugins/formcraft/file-upload/server/content/files/1608b8dea487cc---fokirud.pdf
    • https://www.eoluk.com/wp-content/plugins/super-forms/uploads/php/files/1jtmt6t4pd475kb2s6k4pu41m3/81062354766.pdf
    • http://bidmitt.com/img/files/file/wabokuxokiw.pdf
    • http://conwaychristian.org/wp-content/plugins/formcraft/file-upload/server/content/files/16085c432aca13---nitomu.pdf
    • http://www.euro-fly.eu/userfiles/files/17620594282.pdf
    • http://sewakendragroup.com/userfiles/file/30685031689.pdf
    • https://www.spreefahrten-berlin.de/wp-content/plugins/super-forms/uploads/php/files/5poa0ijvs4d5oj45atdk2216je/40106280710.pdf
    • https://tiguan-wiki.ru/file/69465596119.pdf
    • https://broadstripe.com/wp-content/plugins/super-forms/uploads/php/files/0efed9aa87abe2ef986a55826a047fdf/83233411760.pdf
    • http://www.bridalchapel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b7a5157eac1---kopunavobefiwawilemuzotog.pdf
    • https://www.a2zmedical.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160ac1a0d7c107---fibew.pdf
    • https://www.formwork.co.uk/wp-content/plugins/super-forms/uploads/php/files/mndnqdmdaqfc7r539ki342j36v/72327005805.pdf
    • https://roadtoring.com/wp-content/plugins/super-forms/uploads/php/files/606b12d0b5bd56f8cde55aff692b72f1/jodetomedakokobetu.pdf
    • http://chagatea.ru/wp-content/plugins/super-forms/uploads/php/files/fa3329e8ef8ab9a871e814a52a5a4a13/lomogiwariguzevef.pdf
    • https://dezsredstvompx.ru/wp-content/plugins/super-forms/uploads/php/files/ee1a68fda305d25f51cfef01697bca53/bojuluwiwazuxumupow.pdf
    • http://jagatjyotischool.org/jagatjyotischool/userfiles/file/95167163350.pdf
    • https://swotin.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c0b649c7159---55529137568.pdf
    • http://ijdssymposium.eu/upload/bodejafodotexobivoxusopum.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_off0000dde9.bin
7a58dcc882a7ed41ee0c192493052bd7798f4288d564d60966127308e9dc4a55
pdf-font-stream PDF embedded font (sfnt) at offset 0xDDE9 17036 bytes
font_01_sfnt_off00010a6d.bin
535d42165326b710250d785120df27cf93b498855e2e7e819698efe59bbd7131
pdf-font-stream PDF embedded font (sfnt) at offset 0x10A6D 11100 bytes
font_02_sfnt_off00012428.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12428 16792 bytes