Malicious PDF — malware analysis report

Static analysis result for SHA-256 b4bbb974db1876e6…

MALICIOUS

PDF

72.1 KB Created: 2021-09-26 13:26:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 7b1d6088858dd172d0fbc20ebb5ddb43 SHA-1: 6f0bdd2b6057219d9c82454a3f509cf22ef75158 SHA-256: b4bbb974db1876e6d80bb8f48c8c649e6f3c8a9af3f4280d3bae565ee7de681b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It contains numerous embedded URLs, many pointing to compromised CMS uploads or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, indicating a non-clustered link farm on disposable hosting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9971

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 http://antichigelsi.it/userfiles/files/60848436094.pdf
    • http://bielle-srl.com/userfiles/files/jafezijabusobuzavepapaf.pdf
    • https://samsungklimamodelleri.com/upload/ckfinder/files/70318336320.pdf
    • https://vinamex.info/uploads/news_file/duwigupejedelisumavidazaw.pdf
    • https://ecodiagnost.com/ckfinder/userfiles/files/tokene.pdf
    • https://dijitalsanat.link/upload/files/21393801964.pdf
    • https://swimproject.eu/wp-content/plugins/super-forms/uploads/php/files/a327f6a5e9e7bf7e6d74fcede35cb7aa/vigudawapemetifa.pdf
    • http://archiw.bibliotekalesmierz.eu/img/upload/files/gugerimumepenutopo.pdf
    • https://www.elshandmadedesign.nl/ckfinder/userfiles/files/72890624093.pdf
    • http://alvit-bk.ru/userfiles/file/livutufuxukunumizuxo.pdf
    • http://studiochiodo.eu/userfiles/files/nineladowuxur.pdf
    • http://chargooshads.com/images/upload/files/94010425353.pdf
    • http://remobudostol.pl/pliki/62948253934.pdf
    • http://ballarioarchitetti.eu/userfiles/files/juzalo.pdf
    • http://edituj.cz/res/file/lirifojawusujipama.pdf
    • https://dsodrecital.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138ba192955a---46210971527.pdf
    • https://www.limratechnologies.net/wp-content/plugins/formcraft/file-upload/server/content/files/1613f4e3e9c097---goguwitikubozuje.pdf
    • https://ht-cooling-j3t.com/contents/files/52904536885.pdf
    • http://nhasachthunam.com/upload/files/13761639986.pdf
    • http://royalwedding.jp/images/blog/file/70500448973.pdf
    • http://lidaoxc.com/upload/files/mozodezapewakinobusufiwit.pdf
    • http://thesei.com/
    • http://zamgph.com/uploads/file/040453157080.pdf
    • http://imailbox.nl/images/uploadedimages/file/20062707215.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=among+us+free+online+no+download
    • 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_off0000b46c.bin
1bc5d6f4371e0ed9b15638fc2e620beeb97139546f4e8740400f7bdd246bb5ae
pdf-font-stream PDF embedded font (sfnt) at offset 0xB46C 10764 bytes
font_01_sfnt_off0000cd02.bin
ecd451dc7783d8eb7b166ecac4654fc655c39088d75919b26e5c99357816ad7f
pdf-font-stream PDF embedded font (sfnt) at offset 0xCD02 17628 bytes
font_02_sfnt_off0000fa3d.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFA3D 16792 bytes