Malicious PDF — malware analysis report

Static analysis result for SHA-256 5c55795cc6ac18dc…

MALICIOUS

PDF

82.3 KB Created: 2021-06-26 00:27:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 8d8706fe5e121719d84b6720efe0a5fc SHA-1: 63cb4d1195805a492e1431100377fd5dc290228b SHA-256: 5c55795cc6ac18dc4ae1a0354cad45693172a8b5c0d42fe67a5d98a72b91ddd7
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links, many pointing to compromised WordPress sites, suggesting a link farm designed to redirect users to malicious content. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with techniques used to host malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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://medvor.ru/uplcv?utm_term=clothes+beginning+with+g
    • http://cedresarquitectura.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070e21add668---figeniseb.pdf
    • https://muzeumkonstancina.pl/attachments/file/17236858635.pdf
    • http://saludocupacionalpso.com/home/wp-content/plugins/formcraft/file-upload/server/content/files/160d649b5f1ace---zitojatibadovafo.pdf
    • http://www.naturapreserved.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a0eb47ee252---47152445348.pdf
    • https://vestol.bg/files/file/5408864439.pdf
    • https://alkhairi.co.uk/wp-content/plugins/super-forms/uploads/php/files/b858c91c0b7b6c825b7019e8809b1b31/bamazizerasiweweted.pdf
    • https://cms.blauraum.com/wp-content/plugins/super-forms/uploads/php/files/6bc0e78ae73412d35a3440f3c02477ae/dosijugomolivetozowevon.pdf
    • https://rescue.bg/wp-content/plugins/formcraft/file-upload/server/content/files/160a975888dcbe---xasosedaxugisagerilazedat.pdf
    • http://www.elsecretodelolivo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bc9bd2baa59---40938818767.pdf
    • https://heritagelogs.com/wp-content/plugins/super-forms/uploads/php/files/g85jb78isr5lntf951gf47oavu/51504630064.pdf
    • http://fritz-fahrlaender.ch/download/zebulivasitom.pdf
    • http://anhuizhkj.com/upload_fck/file/2021-6-10/20210610101353531231.pdf
    • https://visionbrindes.com/admin/fckeditor/userfiles/file/25328275527.pdf
    • http://www.advokat.com/app/webroot/img/fck/file/90262238080.pdf
    • http://dabaizhongxue.com/upload_fck/file/2021-5-28/20210528180043673253.pdf
    • https://www.mercato.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160ac7bf1cea80---29327357197.pdf
    • https://aduanaldelvalle.com/userfiles/file/43130262350.pdf
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/f7ki601cd639hk1hagnd9u3sc3/rigiketoduxolibefenafoxox.pdf
    • https://laneopx.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b376b6fa7a---6523568998.pdf
    • https://aashianarealty.com/file/rowalilegu.pdf
    • https://unitedcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085081389034---ninepemezirawibazoxusa.pdf
    • https://youstore21.com/wp-content/plugins/super-forms/uploads/php/files/be56a2ed6637820a9df99dec6ce5356e/tinerozigim.pdf
    • http://classicalgardenornaments.com/uplds/file/duboriripanolofat.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000dbd2.bin
0b5375d9661ec63311c7239371242f7fe17b3fc7b581081419b345c3349faee3
pdf-font-stream PDF embedded font (sfnt) at offset 0xDBD2 18320 bytes
font_01_sfnt_off00010acd.bin
1c1743565e9ef04256702b282bf031400bca4dc6f4f17f8a3e7b67e116193034
pdf-font-stream PDF embedded font (sfnt) at offset 0x10ACD 10384 bytes
font_02_sfnt_off00012254.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12254 16792 bytes