Malicious PDF — malware analysis report

Static analysis result for SHA-256 f8c4683b8bd691eb…

MALICIOUS

PDF

137.1 KB Created: 2021-06-28 19:57:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 1ab78bf6e88645096eae41793c1db11a SHA-1: 26a0c670336aff8574cb73584c03c241ce1a077f SHA-256: f8c4683b8bd691ebb3bca5820e85e9dedb08ea0b418927c18bf0c17cbdd8ab45
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links, many pointing to compromised WordPress sites, suggesting a phishing or malware distribution campaign. The ML classifier and ClamAV detection strongly indicate malicious intent. Although no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of a malicious link farm designed to lure users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9921

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://catamma.ru/uplcv?utm_term=hot+and+sexy+boobs
    • https://liniagdanskzydowo.pl/files/kurojelakoraseg.pdf
    • https://ivfnna.gr/wp-content/plugins/super-forms/uploads/php/files/18d2a85ff6822196001a90642f24a6d5/gawos.pdf
    • http://terapie-psi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1607dc78bf41eb---98681629531.pdf
    • http://www.aluvascientific.com/UserFiles/file/83007276542.pdf
    • https://vickers-electronics.co.uk/wp-content/plugins/super-forms/uploads/php/files/9496a66aa68b3b20b54bfec353278291/sukopapalekalatediro.pdf
    • http://beetsom.com/PROGRAM_FCKeditor_UserFiles/file/55378723760ab65d5d13c1.pdf
    • http://tate79.com/clients/868750/File/pidom.pdf
    • https://lightsourceindiana.com/wp-content/plugins/super-forms/uploads/php/files/94b18731cc3bf1474021b931f4f7db09/duvujukaroxonebidorera.pdf
    • http://americanpetrochemicals.com/customers/CMS-IMAGES/file/42165876461.pdf
    • http://piri-piri.pl/ckfinder/userfiles/files/rotafudulakivekigum.pdf
    • http://edu-family72.ru/content/images/uploads/file/poraxagej.pdf
    • http://www.victorian-manor.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160a479197465a---25977534767.pdf
    • http://dfh-consulting.com/userfiles/file/laragebi.pdf
    • http://tlumacz-lipno.pl/pdrzewiecki/files/jozabaremesomutobig.pdf
    • http://nuocmambason.com/upload/fckimagesfile/f00cf949a3bcda21824a13500019d7ba.pdf
    • https://www.onestopnaturalstore.ca/wp-content/plugins/super-forms/uploads/php/files/inbbu879qnp4ac1drm6vk6qtoe/52538894901.pdf
    • http://bazatalty.pl/wp-content/plugins/super-forms/uploads/php/files/d9b2b50a6106a8255e23cf3c03a9ad9a/74720117562.pdf
    • http://rethabise.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1607d651cd3756---gamivuwafemuwosiwufenedo.pdf
    • https://www.finestkindcharter.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609548cbc41db---kusagenebun.pdf
    • https://prosperitas.be/data/assets/file/10048581328.pdf
    • https://beribuket.ru/wp-content/plugins/super-forms/uploads/php/files/eea44b34c87ab2aca49f2c1b75cc6109/15804788261.pdf
    • http://k1a.ru/images/files/file/rojuvaredufefepoxoniz.pdf
    • http://www.stratcareerservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b9a261d2568---14397694163.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_off0001bc2f.bin
de8112ba638bf5624a8cd5bf6067f9cec4fe221b1edd06d79b218332838de486
pdf-font-stream PDF embedded font (sfnt) at offset 0x1BC2F 10348 bytes
font_01_sfnt_off0001d3b5.bin
1d3b29fec984f8b19cb4a55c74e2c30290c1f2d679e4b5ee12d95c62b62042a8
pdf-font-stream PDF embedded font (sfnt) at offset 0x1D3B5 16528 bytes
font_02_sfnt_off0001feb0.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1FEB0 16792 bytes