Malicious PDF — malware analysis report

Static analysis result for SHA-256 53544728f81081e3…

MALICIOUS

PDF

93.8 KB Created: 2021-07-06 11:28:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 8ce5986380e071df580d594f38384b80 SHA-1: 34d961fe884715eac5fe37ea127198bbee7a2a7a SHA-256: 53544728f81081e3b125e8e40b22c7823560f881f0170b0b980502a2e50aa699
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, indicating a high likelihood of malicious intent. Heuristic analysis revealed it functions as a link farm, directing users to multiple compromised or disposable hosting domains. The presence of numerous URLs, many embedded within the document's structure, strongly suggests a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9918

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://irlanc.ru/uplcv?utm_term=half+of+the+body+is+numb PDF link annotation
    • http://elsekmont.eu/userfiles/file/rijipuluzevenejejuzo.pdfIn PDF document text
    • http://subventionsbetrug.de/wp-content/plugins/super-forms/uploads/php/files/o6pnd8h40agfaq649nptov765i/85635369907.pdfIn PDF document text
    • https://sbsoftware.ro/admin/userfiles/file/66395653577.pdfIn PDF document text
    • https://stpetejazz.com/wp-content/plugins/super-forms/uploads/php/files/c5bu5plro1iuiln4l7jm35g47k/98450004287.pdfIn PDF document text
    • http://michardardillier.com/ckfinder/userfiles/files/45186537126.pdfIn PDF document text
    • https://iamluno.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608b9b14739d4---dugigimajubibowal.pdfIn PDF document text
    • https://gearforfree.com/wp-content/plugins/super-forms/uploads/php/files/fiou865oflpjuhrnu6vpcc1clr/vizem.pdfIn PDF document text
    • http://ganan10.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/1608d5c4d8ad81---koxerorub.pdfIn PDF document text
    • https://www.hdcorp.com.br/wp-content/plugins/super-forms/uploads/php/files/vm2ies5gck29ni3ptbub76cb5k/likiwusofolajo.pdfIn PDF document text
    • https://amenagementsoleil.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ee09e5dfa5---46518640344.pdfIn PDF document text
    • https://clinicscrm.com/img/files/41403441951.pdfIn PDF document text
    • https://cffcommunications.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/1609aca24d013a---mulofosezeboloxuto.pdfIn PDF document text
    • http://bahattinburyan.com/userfiles/file/35661233211.pdfIn PDF document text
    • http://densayhongngoai.com/uploads/userfiles/file/nodupolavusugetuwipedatap.pdfIn PDF document text
    • http://wrtour.com/FileData/ckfinder/files/20210603_CF48C3246F9F775E.pdfIn PDF document text
    • http://jockmurray.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084ef714cdb9---21190975427.pdfIn PDF document text
    • http://qboardapp.com/wp-content/plugins/super-forms/uploads/php/files/71910244e468bdbb79fd9836d29e7530/23008929256.pdfIn PDF document text
    • https://www.digitalsofts.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c3dbd728e3a---vufipizoje.pdfIn PDF document text
    • http://xn--dlek-5qa.com/admin/UserFiles/file/94682309078.pdfIn PDF document text
    • https://gangwontaxi.com/FileData/ckfinder/files/20210625_19F4EF4AEB6544FF.pdfIn PDF document text
    • http://berbun.com/user_img/file/89313409609.pdfIn PDF document text
    • https://bestmiamiturf.com/wp-content/plugins/super-forms/uploads/php/files/3049df22f2b072a89b1efc7ee67802a0/mutesojo.pdfIn PDF document text
    • https://cristiandellavedova.com/wp-content/plugins/super-forms/uploads/php/files/7hmk8f8b4t5sup3d4qk4jvsps5/15094976307.pdfIn PDF document text
    • http://krevue.cz/UserFiles/File/21811001315.pdfIn PDF document text
    • 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_004_off000134d7.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x134D7 17920 bytes
SHA-256: 346f835d98e7635a878cbff3c745c40b5d4b4ccc01f68c77b6cbe4bb98ac698f
font_00_sfnt_off0000f2b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2B0 16244 bytes
SHA-256: 0e7fa46b43b7d5dccf1c2227fb9f1aa57562956175af9c5c631c53209ba8ebf9
font_01_sfnt_off00011cc6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CC6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_03_sfnt_off000150ae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x150AE 10864 bytes
SHA-256: e862b20088fbaeab12350757bb571d0bf9fcbe6615499a9b384ba399ca732a82