Malicious PDF — malware analysis report

Static analysis result for SHA-256 4f3694d9400c0503…

MALICIOUS

PDF

76.1 KB Created: 2021-09-10 04:25:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: ce6d856a3660ec33cbdc8aed7c63ce83 SHA-1: 674fe8ac87fd2130ccb2904835106be117980084 SHA-256: 4f3694d9400c05030c687f4292b46d0a8d6c9b9f75ef43f967e3112a5d41544c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as a phishing trojan. The document contains numerous external URIs and links to compromised CMS uploads, suggesting it is designed to redirect users to malicious websites. While no scripts were explicitly extracted, the PDF structure and the nature of the URLs indicate a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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://medvor.ru/uplcv?utm_term=discrete+mathematics+kenneth+rosen+pdf
    • https://dfa-finanz.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613522250c300---65644962263.pdf
    • http://apvn.info/userfiles/file/zulusakenusivajosulenawoz.pdf
    • https://stpeterscbs.ca/ckfinder/userfiles/files/26664645729.pdf
    • https://fatheragneliti.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139b892cea9f---makoxirom.pdf
    • http://3gr-group-com.gbintl.com/ci/userfiles/files/tezek.pdf
    • https://somos.co/dleyes/admin/fotos/file/69185825921.pdf
    • https://dlt-nkp.com/fileupload/file/13930571530.pdf
    • https://deesudcoolingtower.com/userfiles/file/88690344967.pdf
    • https://www.spoton.pet/wp-content/plugins/super-forms/uploads/php/files/kka4mdtc68c9dp3h583uvdp4k1/zakimejimegonalixu.pdf
    • http://zvezda-rostov.ru/ckfinder/userfiles/files/moxamepoditidifesulirewoj.pdf
    • http://www.unidacardoso.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1612f59fba4cbb---35466168252.pdf
    • https://tallerescarrion.com/uploads/file/80494971946.pdf
    • http://www.skk.com.hk/admin/ckfinder/userfiles/files/46337319002.pdf
    • http://metrocars.london/survey/userfiles/files/dizunavetij.pdf
    • http://nikkenj.com/userfiles/file/nuxozusewaradimugejutuvod.pdf
    • http://fu-xin.tw/uploads/files/202109072333447412.pdf
    • http://kolesnikov.pro/ckfinder/userfiles/files/46881750312.pdf
    • https://cplastik.net/data/cms/file/20853075423.pdf
    • https://whitepalacegrill.com/userfiles/peguxefasevobimedetep.pdf
    • http://www.agrosystem.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16130dde410d86---96896780199.pdf
    • http://baovekhucongnghiep.com/upload/files/76886404240.pdf
    • https://f1com.ge/wp-content/plugins/super-forms/uploads/php/files/91b6e5284c3834d5dcf898892c99e485/70293103784.pdf
    • http://aptekadc.pl/userfiles/userfile/2175134549.pdf
    • https://ice-group.pl/userfiles/file/pesupulovamavikezujas.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_off0000c90c.bin
f4a57b8b172225c17008752ef09bf8da7d2054613f02e7bf90798fbe7ee3d9ac
pdf-font-stream PDF embedded font (sfnt) at offset 0xC90C 15872 bytes
font_01_sfnt_off0000f16e.bin
1ea150158b924b04d0d61496c8bbe182c3d4787438e8df21bf04cdaec69c239b
pdf-font-stream PDF embedded font (sfnt) at offset 0xF16E 10932 bytes
font_02_sfnt_off00010a9b.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10A9B 16792 bytes