Malicious PDF — malware analysis report

Static analysis result for SHA-256 923959d21b16c1ec…

MALICIOUS

PDF

86.3 KB Created: 2021-07-05 10:45:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 276be04a7eeaccb23e05405dd8afcdcc SHA-1: a029665f2d81ff8bfec7dfb7b6d3bb9421d1f95e SHA-256: 923959d21b16c1ec05ef0821921b4336f4c91fcbb3ca134f7fc36c41c7f7315b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document was flagged by ML classifiers and ClamAV as malicious, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm, with numerous URLs pointing to compromised CMS uploads and disposable hosting, suggesting an attempt to distribute or host malicious content. While no scripts were explicitly extracted, the nature of the link farm and the detection suggests it may be used to lure users to phishing sites or download further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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 http://irmascaritasdejesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607018543a3a8---bejip.pdf
    • https://jclifeschools.org/wp-content/plugins/super-forms/uploads/php/files/8e48abb4c4103e66d5bda14dbe5dbfc9/21699533636.pdf
    • https://www.brunosistemi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609476fd2444a---dedasis.pdf
    • https://spherule.org/wp-content/plugins/super-forms/uploads/php/files/f4dc451ba7cf3c1b6993cae1653e0039/68409920460.pdf
    • https://amenagementsoleil.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c9048b3639---16590613449.pdf
    • http://computergramm.com/userfiles/file/vizisuwenapujogiwuwil.pdf
    • http://facilitymanagementassociates.com/survey/userfiles/files/gilivafine.pdf
    • http://akgikorea.com/file_upload/fck_upfile/file/51809815769.pdf
    • https://cms.blauraum.com/wp-content/plugins/super-forms/uploads/php/files/048e5423ff0857d91544b6aca6853eb4/zawimuzetisaxalerebov.pdf
    • http://dossalas.com/wp-content/plugins/super-forms/uploads/php/files/c26e226a7382327544fc6ab0bd0ec8a1/luxiboxidugixus.pdf
    • https://pypconsultores.mx/userfiles/file/75206550961.pdf
    • https://www.criteriainvest.com.br/wp-content/plugins/super-forms/uploads/php/files/ng0viq80ve2q1qts3uol395rsd/goxekugomalovogumodil.pdf
    • http://polskienarty.pl/data/aktualnosci_imgs/file/xokonedumosu.pdf
    • https://eitmedu.in/ckfinder/userfiles/files/88076820183.pdf
    • http://dailyliving.nl/ckfinder/userfiles/files/xitafuzusiva.pdf
    • http://www.dadosefatos.net.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609f532a60799---78705078155.pdf
    • http://ketoanaca.com/uploads/image/files/22929432439.pdf
    • http://erkerlaender.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606fc549a8b3b---28940865746.pdf
    • http://irinaburmistrova.ru/files/24281748777.pdf
    • https://stbenedikt.ch/userfiles/files/posipesenemaniriniwusef.pdf
    • https://jxloanchien.com/style/postimage/file/kudagatudujunevopuzig.pdf
    • http://www.climatisur.com/ckfinder/userfiles/files/68109126413.pdf
    • https://yuktiedu.com/wp-content/plugins/super-forms/uploads/php/files/be36ce43dc017650e00da4cafe3c5ffc/92059185754.pdf
    • https://3dreamstudios.com/wp-content/plugins/super-forms/uploads/php/files/fef8cbc8f97901c95bd3321c429704e0/jigofovovonivewef.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=how+to+cite+when+paraphrasing+apa
    • 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_off0000ec93.bin
ac11dc625a015dbe7a2b49e9392b1c15c01ca458c5e2034e35bc96629ea72047
pdf-font-stream PDF embedded font (sfnt) at offset 0xEC93 10684 bytes
font_01_sfnt_off00010510.bin
15e742df5b3589c8abc3b411d4e5e28c19a5d6c80746e0c4f38ca66a8bfac344
pdf-font-stream PDF embedded font (sfnt) at offset 0x10510 17308 bytes
font_02_sfnt_off00013235.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13235 16792 bytes