Malicious PDF — malware analysis report

Static analysis result for SHA-256 88e25bef58f2158e…

MALICIOUS

PDF

87.8 KB Created: 2021-06-25 13:47:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: 7dc82c690b3320ab688f1cf86cce5bff SHA-1: 94092dba600018f7f11cc9710b2154db3bd15c15 SHA-256: 88e25bef58f2158ef08f1a00fbcda2f5544741508796bb8f961e475e8f27cf5e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to compromised WordPress upload directories or disposable hosting, suggesting a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware delivery via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://archism.ru/uplcv?utm_term=atomic+number+chart+all+elements+pdf PDF link annotation
    • http://erdivigado.hu/userkepek/file/64261619538.pdfIn PDF document text
    • http://anhuifan.com/upload_fck/file/2021-4-28/20210428233718484831.pdfIn PDF document text
    • http://www.thaiboat.net/image/upload/File/17915554324.pdfIn PDF document text
    • https://agrotehholding.ru/wp-content/plugins/super-forms/uploads/php/files/56b958833574dcc2dcd2a4f1c92699fd/nugepijejexisepiva.pdfIn PDF document text
    • http://leaguengn.com/userfiles/file///30381266468.pdfIn PDF document text
    • http://vtvxm.vn/userfiles/file/77624951846.pdfIn PDF document text
    • https://atlanthealth.com/wp-content/plugins/super-forms/uploads/php/files/03796a2efcc12305e102cec3d1e3e1de/18030696872.pdfIn PDF document text
    • https://istocdukkan.com/userfiles/files/77367574960.pdfIn PDF document text
    • http://ozanatalan.com/iboard/includes/userfiles/files/27498611604.pdfIn PDF document text
    • http://augustaelectricalwork.com/editorData/file/zikomagajisisosinepurunu.pdfIn PDF document text
    • http://www.ambredore.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ab02170633---rozogadowobinirukido.pdfIn PDF document text
    • https://heritagelogs.com/wp-content/plugins/super-forms/uploads/php/files/26qd4kg5942hn2mv78iqrr4evt/53465692358.pdfIn PDF document text
    • http://kapelski.pl/userfiles/file/zasupunogageximafanazuzib.pdfIn PDF document text
    • http://ccapostolicchurch.org/clients/1/19/19d200bce63520a637954fb60b162b1a/File/23782478867.pdfIn PDF document text
    • http://www.loockuniformes.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/1606c69c6c6ed5---85683381342.pdfIn PDF document text
    • http://exactblue.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606fba4e37934---32547462801.pdfIn PDF document text
    • http://www.asejnrtigers.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1608b724079b01---44681252024.pdfIn PDF document text
    • http://kioskcondoweb.wpengine.com/wp-content/plugins/formcraft/file-upload/server/content/files/160866dad2d592---fifufosorapotoka.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_off0000f4a0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4A0 17000 bytes
SHA-256: 80dd2a47f88a57affad4f70b25dbcf5fc231f7a27de431063e1a8e9f76f09f58
font_01_sfnt_off00012105.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12105 11108 bytes
SHA-256: c24f1d498771fc5ebfa4b1adef285052aa72ab3c1ab210f81e4c4eb8eb98e16e
font_02_sfnt_off00013a7b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13A7B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1