Malicious PDF — malware analysis report

Static analysis result for SHA-256 a325ac7165402d58…

MALICIOUS

PDF

84.7 KB Created: 2021-09-13 08:12:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 82658d8a0d50ba9c6f16c562e0b9efa1 SHA-1: d537fee0f2c12d546efe8db146866475447807c8 SHA-256: a325ac7165402d5813937a19523697c23f4b85b194871c095e2e298f4aa3d903
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF file was identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It functions as a link farm, with numerous embedded URLs pointing to various domains, many of which appear to be compromised WordPress sites. The 'utm_term' parameter in one of the URLs suggests a potential SEO manipulation tactic to lure users with terms like 'free robux'. The primary attack pattern involves directing users to external, potentially malicious content through a deceptive link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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://www.oschouston.com/osc/wp-content/plugins/formcraft/file-upload/server/content/files/16137699206a93---noxugenazilasobexo.pdf
    • http://hoangminhceramics.com/app/webroot/uploads/files/25819941547.pdf
    • http://iraneto.com/basefile/iranetocom/files/seripe.pdf
    • http://herbwaterthailand.com/userfiles/files/xivipogudoviwerigozemo.pdf
    • https://turbooto.vn/upload/files/denefebelobag.pdf
    • http://gaia-onlus.org/userfiles/file/79250902371.pdf
    • http://vo23.ru/upload/file/23995069605.pdf
    • http://inica.org/files/file///16736967819.pdf
    • http://kuryakyn.ru/userfiles/file/bunidemufonibukede.pdf
    • http://www.miamiairportlimo.net/wp-content/plugins/formcraft/file-upload/server/content/files/161385c7a83ca7---61492158322.pdf
    • https://wlao.on.ca/wp-content/plugins/super-forms/uploads/php/files/0554d7dcc16bc5f734271f4bc890dfbb/zabevanogipati.pdf
    • http://jfhcoaching.nl/userfiles/files/66486340286.pdf
    • https://www.ferienhof-schneider.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613d98189288f---3102041065.pdf
    • https://www.entornopublicitario.com/wp-content/plugins/super-forms/uploads/php/files/aa09fa1774f48019c5678d5d6ef63954/danoxojaserozovo.pdf
    • http://101balkon.ru/upload/files/wexewemexujuxilikasosagi.pdf
    • http://allier-genealogie.org/File:/labokixopolixesoruronaduz.pdf
    • http://mt-filtration.com/uploaded/file/7079872316136e94958615.pdf
    • https://tectrongim.com/uploads/file/zejokagosazivib.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=websites+for+free+robux+2021
    • 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_off0000e6e3.bin
759f3c3165fb7cea955e54821ebc6ecc3792573b46de409fc16d42c30572b477
pdf-font-stream PDF embedded font (sfnt) at offset 0xE6E3 10524 bytes
font_01_sfnt_off0000ff27.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFF27 16792 bytes
font_02_sfnt_off00011739.bin
f9e96739916967a16428d10c28e8395a10cd10e79ca935d0fd45bde6fb466463
pdf-font-stream PDF embedded font (sfnt) at offset 0x11739 18200 bytes