Malicious PDF — malware analysis report

Static analysis result for SHA-256 8f4001f95b75278a…

MALICIOUS

PDF

72.3 KB Created: 2021-09-21 07:00:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: f4a82a24a3f55a01d0c2957d590ae139 SHA-1: 1828fd29d1228f8c6006df43a1781e5cd37a404d SHA-256: 8f4001f95b75278ae97ed43aa6b62532bd5ad65df85b819202e7013016add5d1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised WordPress uploads or disposable hosting, indicating a phishing or malicious redirection scheme. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for credential harvesting or malware distribution. No scripts were extracted, but the PDF structure itself is weaponized to host a link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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=2nd+puc+physics+textbook+pdf PDF link annotation
    • https://doina.md/fckeditorfiles/file/30588477196.pdfIn PDF document text
    • https://www.indee-r.fr/wp-content/plugins/super-forms/uploads/php/files/29e69a232414742a3c94a8d170b67daa/3884016853.pdfIn PDF document text
    • https://ibexquimica.com.br/ckfinder/userfiles/files/63247873952.pdfIn PDF document text
    • http://fantasypartyentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f624a839c2---33461952582.pdfIn PDF document text
    • http://www.valaisconsulting.ch/file/83002109936.pdfIn PDF document text
    • https://gbagencement.fr/uploads/file/66666239384.pdfIn PDF document text
    • http://traiteurluc.com/userfiles/file/34193772214.pdfIn PDF document text
    • https://sandalyecenneti.com/wp-content/plugins/super-forms/uploads/php/files/vl3704sihnf5h4vukcfduf4jpv/dajoka.pdfIn PDF document text
    • http://praconsulgroup.ru/pict/file/45695720553.pdfIn PDF document text
    • http://health-bridge.in/upload/file/zabuwifexenu.pdfIn PDF document text
    • https://pabausa.org/wp-content/plugins/formcraft/file-upload/server/content/files/16130e4c997d6d---bixeme.pdfIn PDF document text
    • http://alda.pl/ckfinder/userfiles/files/87967887118.pdfIn PDF document text
    • http://kfoodntea.com/dataroom/file/majojexezoje.pdfIn PDF document text
    • http://studiotrusso.it/userfiles/files/17407761957.pdfIn PDF document text
    • http://m2m2design.com/userfiles/40830085565.pdfIn PDF document text
    • https://anctools.com/ckfinder/userfiles/files/gimidotakasaji.pdfIn PDF document text
    • http://ambvetsanprospero.eu/userfiles/files/3849783045.pdfIn PDF document text
    • http://zhouzhuank.com/v15/Upload/file/202193230517414.pdfIn PDF document text
    • https://sherwoodchamber.org/ckfinder/userfiles/files/rokejafapejitebuwelebofe.pdfIn PDF document text
    • https://dsodrecital.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133e50236d57---kiwonejoweko.pdfIn PDF document text
    • http://thietbikhachsanvinhhung1.com/upload/files/wozamelerix.pdfIn PDF document text
    • https://madspot.dk/ckfinder/userfiles/files/48039372814.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_off0000b699.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB699 10980 bytes
SHA-256: bdf7465f8c93ebb5aaad045aca07c018080764d1a40d9f1488c6f44277bdffc9
font_01_sfnt_off0000cfe5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCFE5 17212 bytes
SHA-256: fef15b4cc3d6f6fccde662dbeaff553e0ed7b0de70d02a6905b306474defc0c4
font_02_sfnt_off0000fc25.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC25 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1