Malicious PDF — malware analysis report

Static analysis result for SHA-256 c6b87036ac55d42e…

MALICIOUS

PDF

81.5 KB Created: 2021-09-03 18:45:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 11d7a3c2864aa8ce76fd06d15d67949d SHA-1: 98c253cbea619a506d4e70ab960a69e60f12a07b SHA-256: c6b87036ac55d42e03316bae2bdb2c01891c6c98c778af208a8781c0e81a4aeb
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm pointing to multiple PDF files hosted on compromised WordPress sites, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were directly extracted, the structure and URL patterns are consistent with malicious PDF lures.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://amenajarisiconstructii.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1607a0ad96daf5---47149346858.pdf
    • http://michaelwilliamslaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/61930393720.pdf
    • https://castilloexterior.org/ckfinder/userfiles/files/94045520195.pdf
    • https://ariaparvaz.com/basefile/ariaparvazcom/files/tojuke.pdf
    • http://uralinteh.com/uploads/files/54121675220.pdf
    • http://gamjagolla.com/uploads/files/vibevaru.pdf
    • https://ckmandarin.com/uploads/21134813782.pdf
    • http://flambotour.it/themes/userfiles//files/zaromojukeduku.pdf
    • https://247hvac.ca/fabulous1/uploads/files/78373233972.pdf
    • http://pension-erlkoenig.de/img/editor/file/93929541861.pdf
    • https://ecomassage.pt/wp-content/plugins/super-forms/uploads/php/files/rj9id7dmtjufdcva30v6k9c5kn/3592861452.pdf
    • https://maxflowfans.com/userfiles/file/mududuz.pdf
    • http://bobhendrix-law.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/mupopolemizifezenubav.pdf
    • http://asalsold.com/wp-content/plugins/formcraft/file-upload/server/content/files/160826d894606f---gugadila.pdf
    • https://www.popcaffe.it/wp-content/plugins/super-forms/uploads/php/files/292030a3e3e489e7d22083a49b27a84e/64872173526.pdf
    • https://sygimportaciones.com/wp-content/plugins/super-forms/uploads/php/files/4f91jcip40l8pb9h0da62makdr/vazitasewanev.pdf
    • http://raduzhniy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160abf80732ef5---57854052120.pdf
    • https://lllk.ru/wp-content/plugins/super-forms/uploads/php/files/f42ed101e9130355491c2b718496baae/58067934632.pdf
    • https://baodinhsolar.com/wp-content/plugins/super-forms/uploads/php/files/63vik57s07joht3j7onhfm6ago/61350121414.pdf
    • https://gbeequestriansurfaces.com/wp-content/plugins/super-forms/uploads/php/files/lrjvrfe7ut7c4qco0gpofv8k0g/54788938724.pdf
    • https://abril.pe/wp-content/plugins/super-forms/uploads/php/files/hr73c4crotq1bm547q23kct8bg/18628522351.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=burger+medicinal+chemistry+volume+2+pdf
    • 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_off0000d50e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD50E 16792 bytes
font_01_sfnt_off0000ed25.bin
afdacc4cfeee644120c070768ba0313a7cb3ccbfffc3440719d8d8e350318120
pdf-font-stream PDF embedded font (sfnt) at offset 0xED25 11520 bytes
font_02_sfnt_off00010824.bin
e4a968fbeb0b20f9de92177600069af54ceba716cfc608db8e17fbe268f3cc65
pdf-font-stream PDF embedded font (sfnt) at offset 0x10824 18368 bytes