Malicious PDF — malware analysis report

Static analysis result for SHA-256 c5edff438cc21c2a…

MALICIOUS

PDF

83.2 KB Created: 2021-07-18 19:44:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-15
MD5: 90c6adb5c24ddcc67819865c3c0c4edb SHA-1: 6d59da6c12f340fddf9963ab766748ead13f311a SHA-256: c5edff438cc21c2a91d01b1bf98b615d987c8bf560a4a427994cee08612afb9e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm pointing to compromised CMS uploads and disposable hosting, suggesting it's designed to redirect users to malicious sites. Although no scripts were explicitly extracted, the PDF format and the nature of the URLs suggest potential for embedded JavaScript or other exploit mechanisms to facilitate the redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.cibaospalaser.com/wp-content/plugins/super-forms/uploads/php/files/se3oj4q5larn9tqimoon4bc206/82310803915.pdf In PDF document text
    • https://www.hungarianassociation.com/wp-content/plugins/formcraft/file-upload/server/content/files/16098bb10a28ac---45649411208.pdfIn PDF document text
    • http://www.ferm-matic.fr/upload/file/bizemububobawakalido.pdfIn PDF document text
    • http://www.goldenlantern.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1607d3ace989a3---80118826672.pdfIn PDF document text
    • https://www.pessin-location.fr/ckfinder/userfiles/files/87171723255.pdfIn PDF document text
    • https://deewo.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606efcd388421---zepexujarovupidoxopidu.pdfIn PDF document text
    • https://dijitalsanat.link/upload/files/77809623092.pdfIn PDF document text
    • https://hchoanglong.vn/userfiles/file/nemudajojemuzixudolovel.pdfIn PDF document text
    • https://www.truesdalepainting.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b480b32a5a4---vifomemugukemasunigozifi.pdfIn PDF document text
    • http://xn--l3chcucnqd9c0eua7b1k.com/user_img/files/85560981129.pdfIn PDF document text
    • https://victorybear-info.com/userfiles/files/wevowubanoxisuzi.pdfIn PDF document text
    • http://dejede.com/userfiles/file/26458842524.pdfIn PDF document text
    • http://3duct.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d2ebed05f10---77804529227.pdfIn PDF document text
    • http://nsdadventist.org/FCKData/file/36449558563.pdfIn PDF document text
    • http://artdealer.vn/upload/fckimagesfile/eae5945da14e397517b111bd4a83d934.pdfIn PDF document text
    • http://xboxheerlen.nl/userfiles/file/ragivusajanadobonegusurab.pdfIn PDF document text
    • http://kargiskola.ge/myadmin/ckeditor/ckfinder/userfiles/files/40796538679.pdfIn PDF document text
    • https://pharmnet.cz/ckfiles/files/files/8991040996.pdfIn PDF document text
    • https://provisionsinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a6550df050f---99541505929.pdfIn PDF document text
    • https://nikosdimos.gr/userfiles/file/76791906008.pdfIn PDF document text
    • https://dongytueduc.com/wp-content/plugins/super-forms/uploads/php/files/akhp7kqstv5l7q8o1ot2i1s31n/97462639419.pdfIn PDF document text
    • http://ha-sine.com/d/files/bitofebusewodakasifo.pdfIn PDF document text
    • http://kasargod.net/uploads/file/4946896665.pdfIn PDF document text
    • https://jgmurphy.com/wp-content/plugins/super-forms/uploads/php/files/bb1909c40073c57a5cdef4782a65ab8b/fudipago.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=hand+in+kneadPDF 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_off0000e80f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE80F 16352 bytes
SHA-256: 8f527aaedb5dea7c97eda464fba934f4e4725606b6aa9abee55146c89211aa71
font_01_sfnt_off0001126e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1126E 9792 bytes
SHA-256: 3628a4f60dd42f587d2735573ddc6c469729e46cb59da70f723f0c7d3da0507c
font_02_sfnt_off000127da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x127DA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1