Malicious PDF — malware analysis report

Static analysis result for SHA-256 91e547c187016566…

MALICIOUS

PDF

95.8 KB Created: 2021-07-06 22:34:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: f4e929bc91043bee63874e197b857e82 SHA-1: d5d8a5777d106a2070fb9986a8dee658a03ecc69 SHA-256: 91e547c187016566ff84983dbe385a2562e9763035c4353838bc22f257d28a6b
156 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics as malicious, including a critical ClamAV detection and an ML classifier. It contains numerous links pointing to compromised WordPress upload directories, suggesting it's part of a link farm designed to redirect users to malicious content. The presence of these links and the overall structure indicate a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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.predoisiasociatii.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1608bffb692849---namirejuf.pdf In PDF document text
    • https://www.chartsunlimited.com.ph/wp-content/plugins/formcraft/file-upload/server/content/files/1606c7f4006f26---33768123326.pdfIn PDF document text
    • http://www.radioemka.com/wp-content/plugins/formcraft/file-upload/server/content/files/160749593c2022---65858279542.pdfIn PDF document text
    • https://zlatartopalovic.rs//files/xuzilujevuwixe.pdfIn PDF document text
    • http://www.nbrownies.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160afb5dc9b91a---54337778048.pdfIn PDF document text
    • https://www.hagensmarketing.com/wp-content/plugins/formcraft/file-upload/server/content/files/16098af049131a---23128725365.pdfIn PDF document text
    • https://canadiancontractorservices.com/wp-content/plugins/super-forms/uploads/php/files/lne9f86qt9im23uctnn9o6upt1/lemulawanulipazavofeda.pdfIn PDF document text
    • http://compie.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160dda36b8ff3c---jisala.pdfIn PDF document text
    • https://www.colegiodesafio.net/home/wp-content/plugins/formcraft/file-upload/server/content/files/160afda255741a---delukavonogifujige.pdfIn PDF document text
    • http://matrixuniverzum.eu/wp-content/plugins/formcraft/file-upload/server/content/files/16083b9121ab25---84965214572.pdfIn PDF document text
    • https://astek-telem.fr/userfiles/file/81017173882.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b54567b6cee---8282625621.pdfIn PDF document text
    • http://atlantichomeportugal.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c8e11db3247---sapalodoj.pdfIn PDF document text
    • https://kindliving.org/wp-content/plugins/super-forms/uploads/php/files/tmp/fiwasigitejivavigota.pdfIn PDF document text
    • https://roweryelectra.pl/app/webroot/uploads/file/16213972801606.pdfIn PDF document text
    • http://www.sensible-seeds-premium.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a16f4ebb633---jisoganoruvabokedo.pdfIn PDF document text
    • https://cooperspick.com/files/fepeda.pdfIn PDF document text
    • https://masterok-kovka.ru/wp-content/plugins/super-forms/uploads/php/files/d41471e9ede34b65ce5be2363299018c/51601685937.pdfIn PDF document text
    • http://phantasos.org/userfiles/file/42108332241.pdfIn PDF document text
    • http://chinajnbt.com/images/upload/File/86622274429.pdfIn PDF document text
    • https://psychotherapie-dr-albrecht.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608d456ef0808---vivukuxixivowaneduzujise.pdfIn PDF document text
    • https://monyetmesum.com/contents//files/wavinif.pdfIn PDF document text
    • https://www.davidcosz.de/wp-content/plugins/super-forms/uploads/php/files/1av5bo7vot4ct9v2bd53494u9q/binepo.pdfIn PDF document text
    • http://cbelmira.com/wp-content/plugins/super-forms/uploads/php/files/vq25hjdtr984tb3okfmplmtap6/soxavafubexajadujabutiz.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=who+was+the+very+first+president+before+george+washingtonPDF 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_off00010fc5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10FC5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000127dc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x127DC 11132 bytes
SHA-256: 13f611d562c6083f20ea3d8819fb2c2d306987e475e34737816b11f926890caa
font_02_sfnt_off00014172.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14172 17408 bytes
SHA-256: ffad0eeac2bdba8ba0840313c1faf64b34871894b86a132bde769e6bc8dae13e