Malicious PDF — malware analysis report

Static analysis result for SHA-256 cac457c491c38177…

MALICIOUS

PDF

89.2 KB Created: 2021-06-25 17:38:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: df062e1b8854a5ddb6641dcd5d24ca37 SHA-1: 19a9ea4316b6558926d7f23f5dd2f821cbcc9c11 SHA-256: cac457c491c381772c301b4448ac7e171fe8e1bd7814b199ac72dcfbac62911b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The PDF file was flagged by ClamAV as a phishing trojan and by an ML classifier. It contains numerous links, many hosted on compromised WordPress sites, which are likely intended to redirect users to malicious content. While no scripts were explicitly extracted, the presence of embedded URLs and the nature of the heuristics suggest a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

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 http://audiomaster.se/wp-content/plugins/formcraft/file-upload/server/content/files/160a55b02df84f---zelilubuwibege.pdf In PDF document text
    • https://chmelo.hu/sites/default/files/file/jubozokirorikaxu.pdfIn PDF document text
    • https://www.capitalroofingct.com/wp-content/plugins/formcraft/file-upload/server/content/files/16089e05d9129f---notiz.pdfIn PDF document text
    • https://sailstudy.in/ckfinder/userfiles/files/renowibenirido.pdfIn PDF document text
    • https://www.grecosalesinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ce90906121---22214345117.pdfIn PDF document text
    • https://bursakaynak.com/userfiles/file/zapomid.pdfIn PDF document text
    • http://duepassidalcentro.it/userfiles/files/31312833833.pdfIn PDF document text
    • https://www.idahomedia.com/wp-content/plugins/super-forms/uploads/php/files/320d7d54d0e141a5e856028bebba416e/jumezejimopusotuxugibu.pdfIn PDF document text
    • http://raduzhniy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160be65adda4de---bijisogor.pdfIn PDF document text
    • https://sevsport.info/wp-content/plugins/super-forms/uploads/php/files/8690cff1c9b4bcffe71261272dcc3bda/26962956346.pdfIn PDF document text
    • http://yule-sign.com/upload/editor/file/20210601125502.pdfIn PDF document text
    • http://iwish-cosmetics.com/wp-content/plugins/formcraft/file-upload/server/content/files/160871f640ad99---xovus.pdfIn PDF document text
    • http://kennedy-jackson.com/clients/f/f7/f78508644b517540cdb1549d93860f53/File/mogirelolovubatipugatitif.pdfIn PDF document text
    • https://prosegik.com/wp-content/plugins/super-forms/uploads/php/files/cfc2376d7c62d3e34f3a9834e1085020/61467205302.pdfIn PDF document text
    • http://hglobaltour.com/FileData/ckfinder/files/20210611_2E5994A91132EE22.pdfIn PDF document text
    • https://nuregio.de/wp-content/plugins/formcraft/file-upload/server/content/files/160bd38fbed267---92292379328.pdfIn PDF document text
    • http://www.marcado.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16094587f1860f---gupusefuxoxuditu.pdfIn PDF document text
    • https://www.opdrrustukalac.com/wp-content/plugins/formcraft/file-upload/server/content/files/160759a1faf52e---34358087767.pdfIn PDF document text
    • https://sancarspune.com/wp-content/plugins/super-forms/uploads/php/files/7085336f5d781683d16849e215adc3c3/puruto.pdfIn PDF document text
    • https://webmodels.studio/wp-content/plugins/formcraft/file-upload/server/content/files/1606f18d74141f---podabokusuvubuwukilum.pdfIn PDF document text
    • http://firegallery.ru/img/upload/muwixururafejexas.pdfIn PDF document text
    • http://rydelko.pl/userfiles/file/ferirumukujakuxaw.pdfIn PDF document text
    • http://www.sparkprototypes.com/wp-content/plugins/formcraft/file-upload/server/content/files/160712f7a20af6---gokatamiwefodedoputebeli.pdfIn PDF document text
    • https://acronimocostanzo.com/userfiles/file/36670654088.pdfIn PDF document text
    • https://aldea.work/wp-content/plugins/super-forms/uploads/php/files/7585e4966b99bdd7f3704ceca9c376da/27647711141.pdfIn PDF document text
    • http://projectbudapest.hu/wp-content/plugins/formcraft/file-upload/server/content/files/1606cb6f1235b1---49519245750.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BkSY9tpko7c/uplcv?utm_term=probability+and+compound+eventsPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f576.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF576 11096 bytes
SHA-256: 26607115eb78368dfd115cb97bd16b027054a74d2320e1c67fc1df7adb538f6f
font_01_sfnt_off00010f1c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F1C 18248 bytes
SHA-256: 194c486b1e4393b94a3293701d5cbec47e3813023ea50e6c436b84f8bca4a0d3
font_02_sfnt_off00013f82.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13F82 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1