Malicious PDF — malware analysis report

Static analysis result for SHA-256 36aa845df5da9d65…

MALICIOUS

PDF

87.7 KB Created: 2021-07-04 23:24:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: b801164f1508a4cb73119dadc099f9a3 SHA-1: f75a6e08ae14d022d52aa04356002db6851c6d1b SHA-256: 36aa845df5da9d65f4626a944e5c81e49205d16b7ad8027c71fc49830f58f566
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is identified as malicious by ML classifiers and ClamAV, with heuristics indicating it functions as a link farm on compromised CMS uploads. The document body, though heavily obfuscated, combined with the 'SE_INVOICE_LURE' heuristic, suggests a phishing or scam attempt. The presence of numerous URLs pointing to PDF files hosted on various websites indicates an attempt to redirect users to malicious content, likely for further exploitation or credential harvesting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 7

  • 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.
  • Fake invoice / payment lure low SE_INVOICE_LURE
    Document contains invoice or payment language paired with an action verb — useful context when combined with link, macro, or attachment indicators
  • 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://bistro-8.com/wp-content/plugins/super-forms/uploads/php/files/98bbfdf1b48a9e3fa12ed8e6eaf53efd/diwevexenipovubabigelut.pdf
    • https://kalatranslation.co.uk/wp-content/plugins/super-forms/uploads/php/files/qv9se8cpv75muupu1chv4rqk54/rugojogowawixi.pdf
    • http://imreelectric.sk/uploads/file/49037248728.pdf
    • http://rufullthrottle.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a5cf5f2709---57388717114.pdf
    • http://stopasbestos.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160750f8bcc7fe---pipewawujof.pdf
    • https://www.formwork.co.uk/wp-content/plugins/super-forms/uploads/php/files/o257o9t1bv5kp27g2gjfirv2d2/wapavuwujafuk.pdf
    • https://www.golaw.net/wp-content/plugins/formcraft/file-upload/server/content/files/160c509faa8a91---95802412439.pdf
    • http://sunrui-ti.com/d/files/2575705082.pdf
    • https://luxartparquet.com/wp-content/plugins/super-forms/uploads/php/files/962ec77e674f99603b8e9be30bf01099/jolumozeja.pdf
    • https://zhansq.cn/upload/file/14587367103.pdf
    • http://dossalas.com/wp-content/plugins/super-forms/uploads/php/files/53ae108fb402cb4b14917a1437ce64df/74067909313.pdf
    • http://amwordpress.org/wp-content/plugins/formcraft/file-upload/server/content/files/16077525788b84---27968623680.pdf
    • https://www.sidertest.it/wp-content/plugins/formcraft/file-upload/server/content/files/160c8625dabf15---punobutokawibupoxuj.pdf
    • http://sunarfactory.com/userfiles/files/towazofogajatapebo.pdf
    • http://jpcadonate.com/clients/4/48/4863a0bac697dd4b44f4a1b1fb44835f/File/davulupuvatinedevikazewa.pdf
    • https://playerpress.com/ckfinder/userfiles/files/10586235165.pdf
    • https://earthchartercities.org/wp-content/plugins/formcraft/file-upload/server/content/files/16074b1ca0de44---dukizukoweb.pdf
    • http://www.combatsim.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1607870f511df3---kitajulexodavenob.pdf
    • http://www.barankayalar.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160b4948eb6e2b---xutivodarodin.pdf
    • https://xn--78-6kce7dfhb9dwb.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/0df22732a2ce0332800207ff9c7a56bf/xunisawazilejo.pdf
    • https://maugli24.ru/wp-content/plugins/super-forms/uploads/php/files/dc7a56197c84367394319f93e12a3d00/63856068150.pdf
    • http://biaikatolikus.hu/files/file/jasesofogope.pdf
    • https://tcufroghouses.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c77b83e5e91---91869120981.pdf
    • https://bikinibody.be/wp-content/plugins/super-forms/uploads/php/files/dp1q54uho4t2ag05gcevjt911j/75579906246.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=how+to+see+posts+from+a+private+ig+account
    • 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_off0000f43a.bin
3d94f22bf55b95c95b2d90c30535294e1a458f9530548e7e91749e2450f2b22c
pdf-font-stream PDF embedded font (sfnt) at offset 0xF43A 16724 bytes
font_01_sfnt_off00011f88.bin
973e04533323a18ca9e94eea9affcb540932ea7b13c6e60c874fdec8c397a493
pdf-font-stream PDF embedded font (sfnt) at offset 0x11F88 11020 bytes
font_02_sfnt_off00013943.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13943 16792 bytes