Malicious PDF — malware analysis report

Static analysis result for SHA-256 cd71b96c91944a59…

MALICIOUS

PDF

84.6 KB Created: 2021-08-11 15:28:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: c442f5e1787035ab50254cde21de8139 SHA-1: f033eff9731475a12a2611ea9908104878a601ba SHA-256: cd71b96c91944a59115b1233a1e55987c61072a9f4c49e454827061c90f0b2dd
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of external links, many pointing to compromised WordPress sites, indicating a link farm designed for phishing or malware distribution. The ML classifier and ClamAV detection strongly suggest malicious intent. Although no scripts were explicitly extracted, the nature of the link farm and the presence of external URLs suggest it is intended to lead users to malicious content, likely via a spearphishing attachment vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://crewmak.ru/uplcv?utm_term=como+falar+em+publico+livro PDF link annotation
    • http://terapie-psi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160bb67e3549cb---3806681697.pdfIn PDF document text
    • https://mariellatriolo.it/public/file/23780666678.pdfIn PDF document text
    • https://pabausa.org/wp-content/plugins/formcraft/file-upload/server/content/files/16105392499a90---jamubiluranifetojapalen.pdfIn PDF document text
    • http://alphanaturehk.com/userfiles/file/gexojuwupadanelafaromu.pdfIn PDF document text
    • http://canvangdientu.com/images/file/9110102336.pdfIn PDF document text
    • https://bienenaktuell.com/sites/bienenaktuell.com/files/file/manufajozoma.pdfIn PDF document text
    • https://xn----9sbccjdbca7cyaieg1a3j.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/7b9fc3003b50ded52c6e0911321807e9/jozufukifasabisez.pdfIn PDF document text
    • http://hopkins1983.com/clients/861771/File/38046875880.pdfIn PDF document text
    • https://samiznojmo.cz/wp-content/plugins/super-forms/uploads/php/files/716691e6ab1938445aa8f13c8e761e29/nadire.pdfIn PDF document text
    • http://www.psstrecno.sk/wp-content/plugins/formcraft/file-upload/server/content/files/16076a473cd858---fogaparajagevixawut.pdfIn PDF document text
    • http://jentretiens.ch/uploadimage/8400535411.pdfIn PDF document text
    • http://constantcontinuity.com/membership/data//files/25172194813.pdfIn PDF document text
    • http://perles-del-beya.com/userfiles/file/72815261640.pdfIn PDF document text
    • http://joyearland.com/ckfinder/userfiles/files/37735888877.pdfIn PDF document text
    • https://mollis.rs//files/sefine.pdfIn PDF document text
    • https://action-roofing.com/wp-content/plugins/super-forms/uploads/php/files/e22395355d951bf0c52a8b8080925cde/97113158876.pdfIn PDF document text
    • http://www.yourhealthyourchoice.org/wp-content/plugins/formcraft/file-upload/server/content/files/161102b1aa7bbb---xepemulozapipofiritugele.pdfIn PDF document text
    • https://www.sgestrecho.es/wp-content/plugins/formcraft/file-upload/server/content/files/16071b523c6c67---70305643540.pdfIn PDF document text
    • http://netpost.vn/upload/userfiles/files/60347218447.pdfIn PDF document text
    • http://cwesp.biz/upload/file/42705843337.pdfIn PDF document text
    • http://plncse.hu/php_data/file/2863163288.pdfIn PDF document text
    • http://ttccid.com/userfiles/files/xujamiz.pdfIn PDF document text
    • https://masterjobintl.com/ckfinder/userfiles/files/jowuse.pdfIn PDF document text
    • http://xn--90ad5ackt1d.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/9ca7f4a74f3dc2cd4281e329586074cc/37568492506.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_off0000e2e8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE2E8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000faff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFAFF 10608 bytes
SHA-256: 61c832fead8345ba8be5e62a696fb457ae66870a8068282aa9c4856dc8eda2e7
font_02_sfnt_off00011304.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11304 19732 bytes
SHA-256: 74b22a8404b312cf17076e4ba49b6d5c2a04f48a79150acb8d90dae071f0f14d