Malicious PDF — malware analysis report

Static analysis result for SHA-256 bfbe548586f66bc3…

MALICIOUS

PDF

88.2 KB Created: 2021-08-07 13:47:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 7b6ce0b803940a595a2e68118a586a41 SHA-1: 61cf5394ec8c00e565530df32137daa4f107ab7f SHA-256: bfbe548586f66bc399cbd7865b9f45cbdab6eb39c06c9172d532a99eb892dac7
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many of which point to compromised WordPress upload directories, suggesting a link farm designed to host malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution through these links. The document body is unreadable, but the heuristics and URL analysis confirm the link farm attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9987

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 http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/160a42c0114103---19524361368.pdf
    • http://bosch-service-center.ru/uploads/files/78468029391.pdf
    • https://kakvkusno26.ru/wp-content/plugins/super-forms/uploads/php/files/71e04e51bf93eb2ce9f846f146557474/87627313071.pdf
    • https://qualitycountscleaning.com/wp-content/plugins/super-forms/uploads/php/files/4c0bb9422b1ed2c3bf6596de047aa66f/45253749796.pdf
    • https://petala.gr/userfiles/file/71568823868.pdf
    • http://labonscafe.com/userfiles/zazukagazozubusijananelix.pdf
    • https://www.sharpeningfactory.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a3c2de4abf3---noferodujuzo.pdf
    • https://choiceenergynetwork.com/wp-content/plugins/super-forms/uploads/php/files/ba86b85ad8ce92007beb799bba428638/83118255523.pdf
    • http://beergolfers.com./blog/images/file/guxunevususapusuforidu.pdf
    • https://readxyz.org/wp-content/plugins/super-forms/uploads/php/files/f10388f60ec20dcdc57439c38ad03f0f/7768217095.pdf
    • http://xn--80ackbssfuieecff0e8c.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/065cj8d9d5m7nja5r7cl2l4836/vitipuvasuxawuwaz.pdf
    • https://presstone.hu/userfiles/file/jafodamerufekipaxak.pdf
    • http://www.jobsincrete.gr/images/_user_na/file/68264637654.pdf
    • http://www.grundys.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1608f162bb161e---nugizukinabokunumode.pdf
    • https://agrotehholding.ru/wp-content/plugins/super-forms/uploads/php/files/bd4d7e30c0df25c58c84dece3ee2b1c3/11480595397.pdf
    • http://evevoyance.fr/adh/.-/file/wamenebis.pdf
    • http://zartmobilia.com/userfiles/file/20210704170950.pdf
    • http://gf-location.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1609b276db7faa---60984472010.pdf
    • http://udclassof1968.com/clients/74076/File/22985495207.pdf
    • https://www.beachesbrewing.com/wp-content/plugins/super-forms/uploads/php/files/0be11b3972870962d08b8f13883f854c/barol.pdf
    • http://bannails.com/fckeditor_userfiles/file/24034519009.pdf
    • https://levin-dent.ru/wp-content/plugins/super-forms/uploads/php/files/f0e3ced9ae90b08f28d6a275a9379914/87491823125.pdf
    • https://loan-financial.com/wp-content/plugins/super-forms/uploads/php/files/2a52fb8a15313688deb00f193e7466ff/66730083944.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=acer+chromebook+spin+311+will+not+turn+on
    • 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_off0000f1f0.bin
79c3b1c42b49a509932481da477dca829adb5fa3a27a0af2e95d043e27a24174
pdf-font-stream PDF embedded font (sfnt) at offset 0xF1F0 11100 bytes
font_01_sfnt_off00010b95.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10B95 16792 bytes
font_02_sfnt_off000123a7.bin
a9131bce77433675a24798f72e4aa76df24f24468af3f2b46c7a62f3e872f1db
pdf-font-stream PDF embedded font (sfnt) at offset 0x123A7 17716 bytes