Malicious PDF — malware analysis report

Static analysis result for SHA-256 4ad0251413b517a4…

MALICIOUS

PDF

77.1 KB Created: 2021-10-04 11:19:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 90eb8dcbedf503adda55872ff377a85d SHA-1: bf80d8257f378274a79d403abe391f286e1033cf SHA-256: 4ad0251413b517a4a77b39325ff39f720cb300db4ca429d73cf5dec5f0431e3e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites utilizing the FormCraft plugin for file uploads. These URLs are indicative of a link farm designed to obscure the ultimate destination, a common tactic in phishing and malware distribution campaigns. The ML classifier and ClamAV detection strongly support a malicious classification.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://www.scanworld.se/wp-content/plugins/formcraft/file-upload/server/content/files/1613427318fc41---defisatujawulu.pdf In PDF document text
    • http://toanthinh.vn/webroot/img/files/11957489987.pdfIn PDF document text
    • https://www.bouwenaaneensterkwerkgeversmerk.nl/wp-content/plugins/formcraft/file-upload/server/content/files/161494a6e4ba24---sejaboxesidan.pdfIn PDF document text
    • http://aiswaryamatrimonials.com/fck_uploads/file/mededemabizarup.pdfIn PDF document text
    • https://papiratisk.cz/soubory/mopexetiwipemimukuxe.pdfIn PDF document text
    • https://tennis94.fr/img/pics/files/bofanupolevakifug.pdfIn PDF document text
    • https://kokomanis.com/contents/files/83486728628.pdfIn PDF document text
    • http://bioaec.com/userfiles/files/1974202410.pdfIn PDF document text
    • http://www.gieskestukadoors.nl/ckfinder/files/files/59331523481.pdfIn PDF document text
    • http://xn--ob0bjxt9h99icicrvkksa421cwwp7hiv4d6a.net/ckfinder/userfiles/files/poromakifasi.pdfIn PDF document text
    • https://saptabangunmanunggal.com/indomobils/upload/file/18369894053.pdfIn PDF document text
    • http://songhandiban.com/uploadfile/file/2021091020132873499.pdfIn PDF document text
    • https://laznia-radom.pl/userfiles/file/xetefazajuzesozik.pdfIn PDF document text
    • http://3e3i.com/UserFiles/file///44525717127.pdfIn PDF document text
    • http://tourbusan.net/FileData/ckfinder/files/20210905_8E683363EB06E026.pdfIn PDF document text
    • https://hamayeshniroo.com/shop/file/4253448170.pdfIn PDF document text
    • http://www.trimbleexpress.sk/wp-content/plugins/formcraft/file-upload/server/content/files/1614b4f4d4b21e---dazaxukebobemusakoxanan.pdfIn PDF document text
    • http://klick-tipp.at/ckfinder/userfiles/publics/files/93688943034.pdfIn PDF document text
    • https://turkihale.com/userfiles/file/In PDF document text
    • https://thailonghoang.vn/upload/files/19328554414.pdfIn PDF document text
    • https://www.geosuiteonline.de/wp-content/plugins/formcraft/file-upload/server/content/files/161504f21d76e8---kutesojazixuganawavubis.pdfIn PDF document text
    • http://viprealestatebrokers.com/userfiles/files/tamotopavevinodenowupetip.pdfIn PDF document text
    • http://www.tiande-global.com/ckfinder/userfiles/files/89789142219.pdfIn PDF document text
    • http://ambulatorioveterinarioilprato.eu/userfiles/files/97269463625.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=how+to+find+the+equation+of+a+line+that+passes+through+a+point+and+is+parallelPDF link annotation
    • 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_off0000c21e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC21E 11100 bytes
SHA-256: 8cea84119530b503517442fd3120de14707b0f1abca88ad38aae5645379d77ec
font_01_sfnt_off0000db60.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB60 19524 bytes
SHA-256: 4b9619e0c6ffe4187e27e4d2b32daa1d4b6de41e77c2ff2ed96b0825b7d513c9
font_02_sfnt_off00010d83.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D83 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1