Malicious PDF — malware analysis report

Static analysis result for SHA-256 b647c522e43af143…

MALICIOUS

PDF

87.7 KB Created: 2021-06-25 23:25:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 29048d61b9b613ce3746ec0267fd62c4 SHA-1: fe13000ddb869f6a21beadc312d1b96ca15b6d2d SHA-256: b647c522e43af143841e4a7567d595f0e07c8bf99d6c2b9ef7a4158c1c0d659d
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file contains a large number of embedded URLs pointing to compromised websites, indicating it functions as a link farm. The ML classifier strongly flagged this PDF as malicious, and heuristics identified it as a link farm on disposable hosting and pointing to compromised CMS upload storage. The primary purpose appears to be redirecting users to potentially malicious content or phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

Heuristics 5

  • 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://wastran.ru/uplcv?utm_term=cpr+for+adults+and+babies
    • http://mazdooradda.com/userfiles/file/53475091631.pdf
    • http://crystalnymph.by/wp-content/plugins/super-forms/uploads/php/files/ffe66bf0ca4146ee63689b5458b90ae5/81962999392.pdf
    • http://xn--80ackbssfuieecff0e8c.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/h7tf444uofn21qscrp35ddptu3/nagetibok.pdf
    • https://www.dishdivvy.com/wp-content/plugins/super-forms/uploads/php/files/2accccb506653dbadeca60da96bce19b/sibolidekodofogakukutis.pdf
    • http://prodesign31.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16092b8ff34e24---78848899385.pdf
    • https://totalyoumovement.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087fcdfa2353---razotaseparodiw.pdf
    • https://alcc.vn/wp-content/plugins/super-forms/uploads/php/files/21dvo0c23kmgpvl5n58tkckd8f/33167583594.pdf
    • https://drivingschoolofnorthtexas.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607acc519f91d---mutogoselidijelovesubud.pdf
    • https://dezsredstvompx.ru/wp-content/plugins/super-forms/uploads/php/files/5befacc0f80a516ea1607d72dbcd6849/wopeborinofuf.pdf
    • http://sonkertrail.org/clients/9/92/9260a3c387aed4615f72c72c3a1da295/File/67607729988.pdf
    • http://bagpack.com.np/wp-content/plugins/formcraft/file-upload/server/content/files/160b4d675dd596---90581853807.pdf
    • http://charivne.info/images/file/83976680921.pdf
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/7ca04021a7545ba549398367d96a8cdf/82334944080.pdf
    • https://cuisinescartier.ca/upload/editor/file/50106917917.pdf
    • http://www.marcado.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16071e45831238---20631945745.pdf
    • http://www.altrus.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1607b1fdf8392c---rititipavaxeravu.pdf
    • http://alnoorcity.com/userfiles/file/25404774645.pdf
    • http://clearlakesd.org/wp-content/plugins/formcraft/file-upload/server/content/files/1609e27ebea981---tunowibot.pdf
    • http://www.sunargrup.com.tr/wp-content/plugins/super-forms/uploads/php/files/opqbhqjbviv27i2bpi10on05i1/damiletimapizotorefeba.pdf
    • http://julieesteban.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079b0efa3335---29340051769.pdf
    • https://www.sabiamente.es/wp-content/plugins/formcraft/file-upload/server/content/files/160c89b850a897---zusewagex.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_off0000f4b5.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF4B5 16792 bytes
font_01_sfnt_off00010ccc.bin
027288c6b778b211cc50f314d7b70b5e05aea93eb5ca0f30f158c07329fc4ba5
pdf-font-stream PDF embedded font (sfnt) at offset 0x10CCC 10760 bytes
font_02_sfnt_off00012570.bin
0ca4ed33bcd23c7dcb5e855814c8c66b78013f101195b88e9559d97af98766f4
pdf-font-stream PDF embedded font (sfnt) at offset 0x12570 16660 bytes