Malicious PDF — malware analysis report

Static analysis result for SHA-256 e816991643f58bfd…

MALICIOUS

PDF

78.6 KB Created: 2021-08-27 06:52:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: a3fd468224353996361afc17a69879c9 SHA-1: 044789e69b93c3a37bb7527fbe0e343e68cc9e03 SHA-256: e816991643f58bfd00a439a04eba45abb87dad79f253191153501161b22602ea
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs that point to other PDF files, suggesting a link farm designed to redirect users. Several heuristics indicate these links are on disposable hosting or compromised CMS upload directories, increasing the likelihood of malicious intent. The ML classifier and ClamAV detection strongly indicate this PDF is malicious, likely serving as a lure for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9988

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 https://allytemp.ru/uplcv?utm_term=relation+schema+and+relation+instance+in+dbms PDF link annotation
    • http://goksirkrupskimlyn.pl/img/upload/files/30277699970.pdfIn PDF document text
    • https://mmagame.com/userfiles/file/vazana.pdfIn PDF document text
    • http://tafgambiatours.com/userfiles/file/99331580909.pdfIn PDF document text
    • https://sunarchegypt.com/userfiles/file/meluxoxeritedeje.pdfIn PDF document text
    • http://hdurmuslar.com/images_upload/files/52447731606.pdfIn PDF document text
    • http://matstravel.ru/userfiles/file/koxugajebudonujijakap.pdfIn PDF document text
    • https://petroblend.com/wp-content/plugins/formcraft/file-upload/server/content/files/160988b8f40d2c---babomemozufetoxaruletomu.pdfIn PDF document text
    • http://burke-gallonfamilyreunion.com/clients/28163/File/juvosomixitu.pdfIn PDF document text
    • http://sinoorchids.com/image/file/fiwenorokigekane.pdfIn PDF document text
    • http://learnazia.com/fck/imagesfile/leviwokujoxaf.pdfIn PDF document text
    • https://luyenthitoeic.info/userfiles/file/ponosegivazezonivoras.pdfIn PDF document text
    • http://gibisch.info/files/files/36252746496.pdfIn PDF document text
    • https://netlandschool.cl/files/2867034192.pdfIn PDF document text
    • https://dentinale.eu/wp-content/plugins/super-forms/uploads/php/files/7bb4153f35e123ff6dfef37fc8440293/27112041829.pdfIn PDF document text
    • https://almuhja.com/ckfinder/userfiles/files/18662183250.pdfIn PDF document text
    • https://wentworthre.com/wp-content/plugins/super-forms/uploads/php/files/1dc305e0740285820a514a0a2f34ba9d/84922540679.pdfIn PDF document text
    • http://dayuntang.com/assets/uploads/ckedit/files/20210802120655.pdfIn PDF document text
    • https://mehreganimaging.ir/images/upload/files/giwig.pdfIn PDF document text
    • http://bagliodeimille.it/userfiles/files/rirawelesipikogamazid.pdfIn PDF document text
    • http://mtlebanon62.com/clients/5/5e/5ee551a8be14a26d7d76bc5e90dd1372/File/xaxajaku.pdfIn PDF document text
    • http://sportingfoundation.com/uploads/file/vatumagiwelapalogibijanu.pdfIn PDF document text
    • https://c4ir.ae/wp-content/plugins/super-forms/uploads/php/files/tqqu2b81kbs3jv4ditr2qrefb4/19709875478.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_off0000cf8b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF8B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e7a2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7A2 10820 bytes
SHA-256: b62edc7de9448c621614895bc023f289dc9fe8f8f0816c200176226a375a4929
font_02_sfnt_off00010057.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10057 16616 bytes
SHA-256: 8035640c027b1b5967087ce7b6c57e2555898383cb24a67bc649158abadf24dc