Malicious PDF — malware analysis report

Static analysis result for SHA-256 08f31912d826841a…

MALICIOUS

PDF

80.0 KB Created: 2021-09-06 10:51:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e3c3b09200b3c4ab4961e61f62fe2383 SHA-1: 35a7616e10a1aed9722612193ed34024deb4aa29 SHA-256: 08f31912d826841a61f6f123fec50b903ed0897bf3b20f8e9b80b1182914654a
156 Risk Score

Malware Insights

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

The PDF contains numerous external links, many pointing to PDF files hosted on various domains, some of which appear to be compromised CMS uploads. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or SEO spam. No scripts were extracted, and the document body was unreadable, so the attack pattern is inferred from the link farm heuristic.

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://sanfrancescovet.com/userfiles/files/gisegazozejifedapotibaged.pdf
    • http://lawyergz.net/uploadfile/files/bineverob.pdf
    • https://chokysitohang.com/Uploads/userfiles/files/27802998891.pdf
    • https://3dreamvr.com/wp-content/plugins/super-forms/uploads/php/files/850b8144ffe69e19d2d239714ec89cca/36064474105.pdf
    • https://vhssirimpanam.org/ckfinder/userfiles/files/lurenedatefutufevopuz.pdf
    • http://blog.crowdly.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a3c3feac5b2---60344036325.pdf
    • https://www.saltriot.com/wp-content/plugins/super-forms/uploads/php/files/3b657ac3af0de749e21bbc7cc6e7c2e3/45605952547.pdf
    • https://a-metal.e-giant.net/archive/file/files/xokotemikobebufa.pdf
    • http://www.segurosfacility.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606cd1dc4d377---masexikusumamavip.pdf
    • http://www.sunaryem.com.tr/wp-content/plugins/super-forms/uploads/php/files/binip8j9n2chcatdfnr66glvp0/nefoposonufegijijozus.pdf
    • https://nowbali.co.id/wp-content/plugins/formcraft/file-upload/server/content/files/160b29045b02b2---17506980055.pdf
    • http://totaleclipsenv.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac9b2439538---muvesozajazafedileberizix.pdf
    • https://textolinguisticsolutions.com/upload/editor/file/jitusimesoxu.pdf
    • http://ednak.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c17994aa808---5227999393.pdf
    • http://artecgroupservices.com/imagenes/file/5851393990.pdf
    • http://doctour.hu/uploads/ckfinder/userfiles/files/jaguripatep.pdf
    • https://altonika.pro/files/fck/file/jufuzerijijijumiv.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a95f397ab52---fodexasedomubivabu.pdf
    • https://marciasmithconsulting.com/wp-content/plugins/super-forms/uploads/php/files/996a436ec7dd8a593f7bbc41bd102a6b/2478541493.pdf
    • https://growmytruck.com/wp-content/plugins/super-forms/uploads/php/files/0044583123af176a812bef8dd239e1c1/lukajir.pdf
    • http://www.ettermanenterprises.com/ckfinder/userfiles/files/17549198957.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=top+notch+fundamentals+second+edition+teacher%27s+book+pdf
    • 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_off0000ce31.bin
72f3ddd980071ae5fd42fb2d2b9ec56c63c8a067de2bc0fea3aeec13f1830c3e
pdf-font-stream PDF embedded font (sfnt) at offset 0xCE31 11216 bytes
font_01_sfnt_off0000e812.bin
04882d3e46d32b8eff81f83ab8827008681f726b22b66d1f1177cd1ebe6697d7
pdf-font-stream PDF embedded font (sfnt) at offset 0xE812 19076 bytes
font_02_sfnt_off000119fd.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x119FD 16792 bytes