Malicious PDF — malware analysis report

Static analysis result for SHA-256 1c8ba0cb2dd8c009…

MALICIOUS

PDF

77.6 KB Created: 2021-08-19 14:58:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: de5d07ba30532a360986cd4e005785a3 SHA-1: 4f9ad5eea8a5181e52e33c93881677d8bc254393 SHA-256: 1c8ba0cb2dd8c009846e4509abff5c3414aee62e002a7ae235464f2cd8463eed
156 Risk Score

Malware Insights

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

This PDF file was flagged as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous links to compromised WordPress sites and disposable hosting, suggesting it functions as a link farm to redirect users to malicious content. The presence of embedded URLs and the nature of the heuristics point towards a phishing or malware distribution scheme, likely initiated via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://nomylo.ru/uplcv?utm_term=fruktcocktail+t%C3%A5rta+med+glasyret
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/1608258a0c96f2---9475001096.pdf
    • http://dui-antidote.com/images/userfiles/file/83917901300.pdf
    • http://www.rlktechniek.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1611b6d1537355---4177614755.pdf
    • https://www.acptechnologies.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ba395b50c9f---42173339519.pdf
    • https://arihantgranites.in/wp-content/plugins/super-forms/uploads/php/files/eju193jfiucrcib25ulkk2fvo4/91890039943.pdf
    • http://andreaslasnik.com/data/files/nodulurobogomobos.pdf
    • http://miyozenemeryville.com/uploads/files/lumosisiminufekox.pdf
    • http://teraval.cz/res/file/puzuvix.pdf
    • http://www.rkcomdesignservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608785b24dbb1---terajeri.pdf
    • http://www.conectadoscomdeus.tv/arquivos/file/mozuwiteno.pdf
    • https://www.sidertest.it/wp-content/plugins/formcraft/file-upload/server/content/files/1606cbfb33faf7---rulafe.pdf
    • http://www.grupohk.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b5170885b11---lupiwoganatojiban.pdf
    • http://salkim.com/userfiles/file/5140130878.pdf
    • https://cepatdaftargroup2.com/contents//files/14625732738.pdf
    • http://bezpieczna-strefa.pl/wp-content/plugins/super-forms/uploads/php/files/d0106c86f062fc703d4ba0d3a86a0974/87892849209.pdf
    • https://tirthmobile.com/wp-content/plugins/super-forms/uploads/php/files/abok21mhafejoe16jfepp6s96a/99255002800.pdf
    • https://caribemed.com/userfiles/file/58706670400.pdf
    • http://co-mit.com/uploads/files/25742822996.pdf
    • http://lafenicealcamo.it/userfiles/files/baleributiwamoduxed.pdf
    • http://www.luminicaambiental.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608ce84e8688f---liwudepifixobumekujita.pdf
    • https://solener.info/ckfinder/userfiles/files/kobibanowewi.pdf
    • https://binarbaid.com/public_html/userfiles/file/mubitogegifaxifofiberuz.pdf
    • http://aksaaydinlatma.com/img/editor/image/file/kudixosulimefaruso.pdf
    • https://www.ayersworthglen.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e8153b6bb9---51473866968.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_off0000ca8f.bin
52b1e62ab5c533fad328059c702a0f13265b37b42cf1df28c2ad097b405556b7
pdf-font-stream PDF embedded font (sfnt) at offset 0xCA8F 16656 bytes
font_01_sfnt_off0000f445.bin
02fa7bc1c8198643fc32fd4f14a72fc494dc51ca14e209dc17fb8c5c8fc790a4
pdf-font-stream PDF embedded font (sfnt) at offset 0xF445 11152 bytes
font_02_sfnt_off00010db6.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10DB6 16792 bytes