Malicious PDF — malware analysis report

Static analysis result for SHA-256 c30a8da4235fe5b9…

MALICIOUS

PDF

87.9 KB Created: 2021-10-05 11:03:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: da600940680d03c2dce4ee439c5ae63a SHA-1: 15b61726a561da2627685830136b4e2078e598fc SHA-256: c30a8da4235fe5b9268e6f276ab42a8c9073b3bb8f03b9d58f11a2adab9d328e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains a large number of external links, many pointing to compromised websites or disposable hosting, indicative of a link farm used for phishing or malware distribution. The ClamAV detection and ML classifier strongly suggest malicious intent. While no scripts were explicitly extracted, the PDF structure and link farm behavior are common in phishing campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://philabc.ru/uplcv?utm_term=letter+for+friend+birthday PDF link annotation
    • https://mallenmediations.com/mallenmediations/images/userfiles/file/34314757855.pdfIn PDF document text
    • https://fulzugaskozpont.hu/files/35148145826.pdfIn PDF document text
    • https://realimpacto.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16149757fafc98---73236279230.pdfIn PDF document text
    • https://giraffeng.net/infodaily/gen-ckfinder/userfiles/files/14733762106.pdfIn PDF document text
    • https://fundacionamigosdelmarcaribe.ong/ckfinder/userfiles/files/tigori.pdfIn PDF document text
    • http://vdi.vn/userfiles/file/72117966081.pdfIn PDF document text
    • http://appinaris.net/ckfinder/userfiles/publics/files/99622575086.pdfIn PDF document text
    • https://supportsystemsvainc.com/home/ssvi/public_html/ckfinder/userfiles/files/36570366120.pdfIn PDF document text
    • https://sabresources.com/FCKuploads/file/zikepevetij.pdfIn PDF document text
    • http://kiavysocina.cz/UserFiles/File/wolejekezonifuzumofa.pdfIn PDF document text
    • http://altadirezione-consulting.it/userfiles/files/vafaxinexe.pdfIn PDF document text
    • http://bukharajohnscreek.com/sites/default/files/file/8538897666.pdfIn PDF document text
    • http://msci.com.ng/wp-content/plugins/formcraft/file-upload/server/content/files/1614f765b46c19---fasumurufojosa.pdfIn PDF document text
    • https://polinagerz.ru/wp-content/plugins/super-forms/uploads/php/files/6et5vesuqqd5r20nf26tptsffh/4291114557.pdfIn PDF document text
    • https://honkakuji.jp/honkakuji/images/ckfinder/files/22556338502.pdfIn PDF document text
    • http://xn--365-pn7mwb654m2qn.com/ckupload/files/kevitujurolaloxobuvukopon.pdfIn PDF document text
    • http://fitnessklub-impuls.pl/uploads/assets/file/28406515668.pdfIn PDF document text
    • https://nonbodepsg.com/uploads/files/56406477412.pdfIn PDF document text
    • http://tianfonmm.com/d/files/vadanososokabit.pdfIn PDF document text
    • http://jfac.kr/ckfinder/userfiles/files/xusijajasobadegafij.pdfIn PDF document text
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614ae82539c8b.pdfIn PDF document text
    • http://flywings.sk/UserFiles/file/34428858085.pdfIn PDF document text
    • https://k-barrierfree.com/FileData/ckfinder/files/20210903_1F23F42E95F10858.pdfIn PDF document text
    • http://krakowska98.com/zdjecia/fck/file/67788730391.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f43c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF43C 18140 bytes
SHA-256: 5cbc40d249955af7abf269d4e0fca5871f497bb71343d87c5aa41a06dde5835b
font_01_sfnt_off00012241.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12241 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013a58.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13A58 10448 bytes
SHA-256: c3b14b4d0784aafc4660cd2f07a2dd0f0827c3f0ae04b48fa9be4e462830efe6