Malicious PDF — malware analysis report

Static analysis result for SHA-256 4bd57382c43c0bc5…

MALICIOUS

PDF

77.9 KB Created: 2021-06-26 22:49:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 8cfde2d66669ea4d76f9d38c78b2d537 SHA-1: 6014e3084bd4627ae1d5d2ef4f538b1ccd381b6e SHA-256: 4bd57382c43c0bc54c9920b5cbabb89f4e3625121779e4b1f723e78910a5e6fb
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised WordPress sites, suggesting a link farm designed to lure users to potentially malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution via these links. No scripts were extracted, and the document body was unreadable, limiting further analysis of the specific lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://jfefood.com/wp-content/plugins/super-forms/uploads/php/files/6a072ed277c8bda6f66c73d7921dcda5/fimud.pdf
    • http://fdscience.com/UPFILE/userfiles/files/tajeximuje.pdf
    • http://stopasbestos.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1609f6c5515eba---torakubefodononew.pdf
    • https://velvetskin.pl/wp-content/plugins/super-forms/uploads/php/files/f122c8eb5a7e92a4117ceee116597308/kemivore.pdf
    • https://fjordancv.info/wp-content/plugins/super-forms/uploads/php/files/12fcd1644d5abd378568682ee235008a/rugusiwafure.pdf
    • https://designclarf.it/file/labivedogojiniro.pdf
    • https://christembassyromford.org/wp-content/plugins/super-forms/uploads/php/files/143f174b888750cfb9311618483f8653/letiworifamexozali.pdf
    • https://www.frankreich-ferien.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160b8e6376fb33---10025043649.pdf
    • http://www.nowsingapore.co.id/wp-content/plugins/formcraft/file-upload/server/content/files/16075cf96ed670---xojuwip.pdf
    • http://hurtglass.pl/upload/file/miraxolokoxidi.pdf
    • http://jinanxintiandi.com/userfiles/files/27399915434.pdf
    • http://www.belladermeestetica.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16088713381627---39217551342.pdf
    • http://rocb-ap.org/file_media/file_image/file/9354928264.pdf
    • http://studiotecnicobonoli.com/userfiles/files/68914416930.pdf
    • https://beribuket.ru/wp-content/plugins/super-forms/uploads/php/files/3d77df2aedc3d834027c04bc2cd8c9c5/nujinemot.pdf
    • http://claudiodauelsberg.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609f0415a939d---83323437276.pdf
    • http://mineraux-et-lithotherapie.fr/ckeditor/upload/files/xesonobesudun.pdf
    • http://www.virtualaid.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160c4e44433ea3---99070852500.pdf
    • http://msslink.ru/userfiles/files/regufumikunevu.pdf
    • http://shs1977reunion.com/clients/41590/File/91610464040.pdf
    • https://mikepromedia.com/wp-content/plugins/super-forms/uploads/php/files/smonj4or0uthgl13bt2in5l023/87496796451.pdf
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/aatf734dmr4ll5nn9s1n8n3gv6/83878394286.pdf
    • https://bmw-zona.ru/uploads/file/xugaw.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=the+symptoms+of+being+human
    • 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_off0000cea5.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xCEA5 16792 bytes
font_01_sfnt_off0000e6bc.bin
b4317468c0c10cdb8b4eddbad68c8189c2ec3733f3122a74e6d4aa90f91a0736
pdf-font-stream PDF embedded font (sfnt) at offset 0xE6BC 10976 bytes
font_02_sfnt_off0000ffe0.bin
87fd93fdae1f6f12f5dc8490bbddbdc93c8b418fdc3269493d29ed94e021df1a
pdf-font-stream PDF embedded font (sfnt) at offset 0xFFE0 16496 bytes