Malicious PDF — malware analysis report

Static analysis result for SHA-256 c21d692a07b52ccf…

MALICIOUS

PDF

84.6 KB Created: 2021-07-05 22:42:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 7b062f51d90170873b6bc55dd6343f75 SHA-1: c4b36bc7fa87cdd2ddd19f7346631d7a215d5a76 SHA-256: c21d692a07b52ccf24eef6b4342b62041eedd3ddc0747d438c99ee310dbea713
124 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The file was detected as a phishing trojan by ClamAV, indicating malicious intent. Static analysis revealed it functions as a link farm, with numerous URLs pointing to compromised WordPress sites hosting other PDFs. These linked PDFs are likely designed to further phishing attempts or distribute malware.

Machine Learning

  • Nyx PDF Classifier suspicious score 0.4741

Heuristics 5

  • 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
  • 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://irmascaritasdejesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b598ea7f89c---67090804618.pdf In PDF document text
    • http://asahiru-ban.com/files/files/87286410564.pdfIn PDF document text
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/f58eml9970i6i0ojh01fb24dj6/fenojubudijato.pdfIn PDF document text
    • https://www.infratechgroep.nl/wp-content/plugins/super-forms/uploads/php/files/c61a87bcbb66d2917814efc0a6e1a216/baxozuzeremomulujinop.pdfIn PDF document text
    • http://www.psstrecno.sk/wp-content/plugins/formcraft/file-upload/server/content/files/160b73dfcdfbd1---witubaxazifojo.pdfIn PDF document text
    • https://benchmarktransitions.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c7bf6d84d36---lumurepasizilu.pdfIn PDF document text
    • https://vildmarksjagt.dk/userfiles/file/zodexogebumen.pdfIn PDF document text
    • http://aristosaigonhotel.vn/uploads/files/20830259931.pdfIn PDF document text
    • https://hmjrgoldhockey.org/wp-content/plugins/super-forms/uploads/php/files/0761b45bba660dec6d89c5c7d491a1cd/funurolidupesov.pdfIn PDF document text
    • http://www.dnevi-sekretarjev.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160c3fb74615e5---xisomikiko.pdfIn PDF document text
    • http://www.ncstarim.com.tr/wp-content/plugins/super-forms/uploads/php/files/udrnphpgr3adr5sdv0mivimkr0/64695029942.pdfIn PDF document text
    • https://motionslam.com/wp-content/plugins/super-forms/uploads/php/files/f66f10808b80316c2b18451e87857786/32705712655.pdfIn PDF document text
    • https://inifd.london/uploads/file/51195446028.pdfIn PDF document text
    • http://halvani.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608b5f1b2e265---lavivuwovofe.pdfIn PDF document text
    • http://amwordpress.org/wp-content/plugins/formcraft/file-upload/server/content/files/160b447998eb0e---72625016304.pdfIn PDF document text
    • https://textosolutionslinguistiques.ca/upload/editor/file/gazegivaxuxetubozajatev.pdfIn PDF document text
    • http://ednak.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bcfc0c61bd6---vofesifilujidopuxota.pdfIn PDF document text
    • http://www.myhhsi.com/wp-content/plugins/super-forms/uploads/php/files/db8fb1d22d5505c07b7dcd1b91d5a041/2332746263.pdfIn PDF document text
    • http://billsky.ee/files/file/kulogorexexorinil.pdfIn PDF document text
    • https://lostsoulsmemorialnj.org/wp-content/plugins/super-forms/uploads/php/files/930aa8045f34d3c445395e7932a5eef0/rimaforuzovosipax.pdfIn PDF document text
    • https://hzautomatisering.nl/userfiles/file/dowomujurubazem.pdfIn PDF document text
    • https://alfa-pechati.ru/wp-content/plugins/super-forms/uploads/php/files/0f43576a90a80d8677aa0a0ce3b3d476/32664377687.pdfIn PDF document text
    • https://clumba-indoor.ru/files/files/pikewobugobuzuwetozileb.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=crystal+field+splitting+of+d+orbitals+in+octahedral+complexesPDF link annotation
    • 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_off0000f212.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF212 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010a29.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A29 11456 bytes
SHA-256: 100ab1923235e234fcdefa9dc2ff982183eebc024aea125cc1d36019949adf00
font_02_sfnt_off0001249b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1249B 17804 bytes
SHA-256: 79edaecf3e531d20730c03bbbbd4bf5659a35192f8c11ff8e61324f596fe70dd