Malicious PDF — malware analysis report

Static analysis result for SHA-256 a557dbcde1ab1641…

MALICIOUS

PDF

69.9 KB Created: 2021-09-02 05:15:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 29d109d72b1d586795b8714376dd8f93 SHA-1: 307369623fce2109519938bcbd9d6bbebfb03a1c SHA-256: a557dbcde1ab16412e2c1d31ffd54e8d69418cde7363d23ca5eff5bb0fbb997f
156 Risk Score

Malware Insights

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

This PDF file was identified as malicious by ClamAV and an ML classifier. It functions as a link farm, containing numerous URLs that point to various websites. Some of these URLs are hosted on compromised WordPress installations or disposable domains, suggesting an intent to lure users to potentially malicious sites for phishing or further exploitation. The presence of multiple external URIs and link farm characteristics strongly indicates a malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://tubietelbar.hu/uploadfile/44171480438.pdf In PDF document text
    • http://technoculture.cz/admin/upload/file/4552023975.pdfIn PDF document text
    • http://amadpich.com/userfiles/file/pawijul.pdfIn PDF document text
    • http://creative-format.com/upload/editor/files/26603354868.pdfIn PDF document text
    • http://www.sunargrup.com.tr/wp-content/plugins/super-forms/uploads/php/files/pioormmueodtrv3ord9hvnqkr1/3416135919.pdfIn PDF document text
    • https://www.gsccn.it/wp-content/plugins/formcraft/file-upload/server/content/files/1608b5e5fec885---gugofojobudirixejim.pdfIn PDF document text
    • https://almoheetmanpower.com/public_html/userfiles/file/risefesivuraxukuv.pdfIn PDF document text
    • https://cmflower-kkc.com/ckfinder/userfiles/files/4491282720.pdfIn PDF document text
    • https://angkorphotographyguide.com/userfiles/file/54501226999.pdfIn PDF document text
    • http://anandtouristcorporation.com/uploads/20741126639.pdfIn PDF document text
    • https://xn--fct8ml6mwue.tw/uploads/files/69737656181.pdfIn PDF document text
    • https://solarconsulting.org/wp-content/plugins/super-forms/uploads/php/files/5968ae2380579c7a3f75fc15fb7f0274/watedazeg.pdfIn PDF document text
    • http://sxhk365.com/uploads/file///tevuwufoke.pdfIn PDF document text
    • http://ewtch.com/upload/files/varomet.pdfIn PDF document text
    • http://zechnerbau.at/images/content/files/wakiramatulunob.pdfIn PDF document text
    • https://x-software.cz/data/file/58112674690.pdfIn PDF document text
    • http://take114.kr/FileData/ckfinder/files/20210726_FA478984EABA58E8.pdfIn PDF document text
    • https://alperbehang.nl/userfiles/file/gofixevodiwamug.pdfIn PDF document text
    • https://hmanagement.net/userfiles/file/37940262361.pdfIn PDF document text
    • http://www.bestlifepolicy.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160b00b83dd2a1---daxiwolikizevamir.pdfIn PDF document text
    • http://ukrainski-rosyjski.pl/userfiles/file/xibilifatusubidif.pdfIn PDF document text
    • http://thailaundry.com/imgUpload/files/24090477289.pdfIn PDF document text
    • http://endustriyelkiralama.com/wp-content/plugins/super-forms/uploads/php/files/t811r896pgf0nr9rn9guqgk17i/8370011401.pdfIn PDF document text
    • https://edinburghpools.com/contents//files/fuxumujomi.pdfIn PDF document text
    • http://objetivovender.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c522fc689ea---25484595195.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=major+theological+themes+of+the+new+testamentPDF 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_off0000b470.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB470 10992 bytes
SHA-256: f8d3d6ca301df9fd2ae545931b1468b4d63c9ec0a4e630703ffc0d7ad2ea9289
font_01_sfnt_off0000cdd3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCDD3 14348 bytes
SHA-256: c9865770b961f151e0b621d5fb8a63b2273627fd152e95401d6b50899f893944
font_02_sfnt_off0000f159.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF159 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1