Malicious PDF — malware analysis report

Static analysis result for SHA-256 dcd838c1f57eb7e7…

MALICIOUS

PDF

77.1 KB Created: 2021-09-07 08:16:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 13fac694b3b42809d66eb46d4b5e1311 SHA-1: 8822c35f635dd92a6cd7c9c0284f8f0cf58f478a SHA-256: dcd838c1f57eb7e77ac2f119bbfedbef09e121d1d9ade2a68d541d5b8c62d69a
156 Risk Score

Malware Insights

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

The PDF document contains a large number of external links, many of which point to compromised WordPress upload directories. The ML classifier and ClamAV detection strongly indicate maliciousness, classifying it as a phishing trojan. The primary attack pattern involves directing users to potentially malicious content hosted on compromised sites, likely as part of a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://www.accidentinjurylascruces.com/wp-content/plugins/super-forms/uploads/php/files/vilgkf1khe9j7l9b2uk9qdoln4/72350638759.pdf In PDF document text
    • https://stewsites.com/wp-content/plugins/super-forms/uploads/php/files/489a5cbb41ee4e911d4d183b8a910779/fozawebipitonajoxel.pdfIn PDF document text
    • https://comodee.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e8cde310d2---43641382391.pdfIn PDF document text
    • https://gk-termopanel.ru/wp-content/plugins/super-forms/uploads/php/files/4169e873ee550facf5437c6916b1e8f0/29310023939.pdfIn PDF document text
    • https://transilvaniafishing.ro/app/webroot/files/userfiles/files/javokasaxovasid.pdfIn PDF document text
    • http://ilturismoinitalia.it/userfiles/files/fozataxed.pdfIn PDF document text
    • http://abimobiliare.pl/pliki/File/43986834777.pdfIn PDF document text
    • http://mramus.com/fck/imagesfile/45739773928.pdfIn PDF document text
    • http://noticiascgnews.com.br/ckfinder/userfiles/files/zuxufujivoduf.pdfIn PDF document text
    • https://www.finestkindcharter.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609f453e72871---21590891291.pdfIn PDF document text
    • http://onlinevay.com/upload/files/87533076852.pdfIn PDF document text
    • http://trungtamsangloc.vn/uploads/ck_upload/files/26349430159.pdfIn PDF document text
    • http://aeskulap24h.de/wp-content/plugins/formcraft/file-upload/server/content/files/160bd72e5a4f65---46912556967.pdfIn PDF document text
    • http://wxhsbl.com/ckfinder/userfiles/files/20210824_084209.pdfIn PDF document text
    • https://dermo.com/wp-content/plugins/formcraft/file-upload/server/content/files/161121028be16e---7306888818.pdfIn PDF document text
    • http://edilgroupdigiovanni.it/userfiles/files/xuvilade.pdfIn PDF document text
    • http://minhnguyenvn.com/uploads/userfiles/file/ritilurus.pdfIn PDF document text
    • http://geomanteia.com/userfiles/files/menagutosugutime.pdfIn PDF document text
    • https://web-sila.ru/wp-content/plugins/super-forms/uploads/php/files/6de551d505e9ee6a523be1307b5eb572/91835711074.pdfIn PDF document text
    • http://ajisushionline.com/uploads/files/87894300234.pdfIn PDF document text
    • https://xn----8sbaavnccwq4am.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/7dea7d4bf1a090ba6db12b368d7b1d60/maveketasujodob.pdfIn PDF document text
    • http://24horasnoar.com.br/ckfinder/userfiles/files/jepuvetujukedogi.pdfIn PDF document text
    • https://bettenbaehren.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606d825843a00---munorufumepomosud.pdfIn PDF document text
    • http://www.cottagegrad.ru/files/file/39978224390.pdfIn PDF document text
    • https://amerismithenterprises.com/wp-content/plugins/super-forms/uploads/php/files/89ee2a8d3e921743a2301b68b9ed86d1/sigis.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=management+of+cooperative+housing+society+pdfPDF 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_off0000ca07.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA07 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e21e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE21E 11292 bytes
SHA-256: a3be6358caf5b4cf8377a930a07655dfa4f478be5a51416f8cb245f10ec117ac
font_02_sfnt_off0000fc4a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC4A 16384 bytes
SHA-256: 5e3afbd1e3e617772767b110637eb2b26895be3271f1da1d748c814201102b79