Malicious PDF — malware analysis report

Static analysis result for SHA-256 aa841fa667ad6c54…

MALICIOUS

PDF

84.9 KB Created: 2021-09-14 14:57:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: c463df60e193541e981ae58070e79922 SHA-1: 4bf62d307d9fe146389336ee9a3f342fd61060c5 SHA-256: aa841fa667ad6c548481338681acf8b93ff16e521c215ca6cd525d6efc658f1f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file was identified as malicious by a ML classifier and ClamAV, indicating a phishing or trojan threat. It contains numerous links to external websites, many hosted on compromised WordPress sites, suggesting a link farm designed to redirect users to malicious content. While no scripts were explicitly extracted, the nature of the links and the heuristic firings point towards a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

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 https://sellos-mecanicos.com/wp-content/plugins/super-forms/uploads/php/files/6efadcbb5c9c56e7954132958c2f1d5a/titejaf.pdf In PDF document text
    • https://weishinclinic.com/uploads/files/202109132152346386.pdfIn PDF document text
    • http://bradzo-ep.com/uploads/files/rikalepujujuragaxibikuf.pdfIn PDF document text
    • http://rapet.hu/files/ridasolofif.pdfIn PDF document text
    • http://beijingxinzhi.com/userfiles/file/20210906173834_1309934640.pdfIn PDF document text
    • http://indcms.testingmachines.com/images/file/13335721384.pdfIn PDF document text
    • http://liburnia.pl/userfiles/file/movitupaseto.pdfIn PDF document text
    • https://andymullinscommercial.com/home/andy/public_html/ckfinder/userfiles/files/81875491350.pdfIn PDF document text
    • http://davidhammerstein.org/ckfinder/userfiles/files/67411949106.pdfIn PDF document text
    • https://lufty.cz/UserFiles/files/vusoruzoxupafo.pdfIn PDF document text
    • http://op-gold.com/ck_image/files/neniwisesiliwozibawuziku.pdfIn PDF document text
    • https://selapro.com.au/application/third_party/ckfinder/userfiles/files/gupifobo.pdfIn PDF document text
    • http://autoscuolauniversale.it/userfiles/files/9243980499.pdfIn PDF document text
    • http://reclaimsplus.com/wp-content/plugins/super-forms/uploads/php/files/90dd8ab0b885127c77538f93028c55e0/bamiwutenuwigupugu.pdfIn PDF document text
    • https://avenirpourtous.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16135e76756585---ramefezudoxi.pdfIn PDF document text
    • https://apra.pl/files/file/67612236763.pdfIn PDF document text
    • http://ersenergy.com/UserFiles/file/79024998207.pdfIn PDF document text
    • http://kondicionery-krasnogorsk.ru/upload_picture/file/68452718796.pdfIn PDF document text
    • https://tecnicadovolante.com/images/file/kuwajuwanirulagugadute.pdfIn PDF document text
    • https://orangcar.com/app/webroot/upload/files/podos.pdfIn PDF document text
    • http://bagiez.com/userfiles/file/xutel.pdfIn PDF document text
    • https://barcelonamedicalcenter.com/files/galeria/files/82913484196.pdfIn PDF document text
    • http://kuresi-kaitori.com/upload/content_pic/files/52868424227.pdfIn PDF document text
    • https://aprenda-atdi.com/uploads/files/14955338800.pdfIn PDF document text
    • http://csc0516.com/userfiles/file/20210901111916_yi5gdo.pdfIn PDF document text
    • http://pcserviszlin.cz/ckfinder/userfiles/files/75682795528.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=fifa+obb+data+2021PDF 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_off0000e68e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE68E 18320 bytes
SHA-256: 9cf12277ea2e9b141a94097f17a04dc4076bcebffd5cd8567eeea8f0c214c29a
font_01_sfnt_off000116d5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x116D5 10208 bytes
SHA-256: 62152fce0571e46fd58245457eb69134024d50c69e2c9f3fe0abf6b43643f713
font_02_sfnt_off00012ddf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12DDF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1