Malicious PDF — malware analysis report

Static analysis result for SHA-256 55c87cf70479d444…

MALICIOUS

PDF

78.5 KB Created: 2021-08-30 05:36:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d046662fcb30ee3897b2de8587fe33cf SHA-1: 27ce86615a4b292a8b3112575deac65f91a6a9d7 SHA-256: 55c87cf70479d444f3fc3bc7fad22e082560781068784d182321e443ab38e057
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as Pdf.Phishing.Trojan. The file contains numerous links pointing to various websites, many of which appear to be compromised WordPress installations used for hosting PDF files. The primary attack pattern involves directing users to these external URLs, likely for phishing or to download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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://ketchas.ru/uplcv?utm_term=ap+computer+science+consumer+review+lab+answers
    • https://relleno-acidohialuronico.com/wp-content/plugins/super-forms/uploads/php/files/9fc6c480cabf4beed1016a8af79bca36/gozuwilema.pdf
    • https://www.3dreamchurch.com/wp-content/plugins/super-forms/uploads/php/files/28031d51d0ce6260ff0b19499337d796/lavutajunozom.pdf
    • http://ahkjt.com/upfile/file/24022321087.pdf
    • http://lightningriskassessment.com/ci/userfiles/files/jajalefesudejajuxigazil.pdf
    • https://funkydrop.shop/wp-content/plugins/super-forms/uploads/php/files/46f530ae17a2d74d8d4fbb83e61df6cc/11998484863.pdf
    • https://www.web2business.pt/wp-content/plugins/formcraft/file-upload/server/content/files/160d4a846bb6fe---xezuvuvugenarazun.pdf
    • http://surrattsville69.com/clients/8/81/8122276c22396d7fa0996010cc369f50/File/vatepebofafojirumawezerat.pdf
    • https://lacecinella.com/writable/public/userfiles/file/voporaziko.pdf
    • http://solyaris.pro/admin/ckfinder/userfiles/files/nowixonopo.pdf
    • https://dptech.vn/uploads/files/81334895342.pdf
    • http://theopenhouseclub.com/wp-content/plugins/super-forms/uploads/php/files/2732fce7c42a7ddd9444bafbc8a080f8/15547798837.pdf
    • https://dedywiredja.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e077df0df1a---53229437093.pdf
    • http://romanakladatelstvi.cz/userfiles/file/57730568551.pdf
    • http://ngnjl.com/userfiles/files/balejaju.pdf
    • https://www.tvmreza.tv/ckfinder/userfiles/files/gibuwizomudinumelaf.pdf
    • http://agriturismofattorialucciano.it/ckfinder/userfiles/files/vozanadej.pdf
    • https://ecoinkworld.com/wp-content/plugins/super-forms/uploads/php/files/f1f14e7c895a2214e47e096f0326ecfd/18489126138.pdf
    • http://topstec.com/d/files/kirizag.pdf
    • https://solidpractise.com/files/userfiles/file/bufogefetedeloralamomad.pdf
    • http://www.zav-mito.si/wp-content/plugins/formcraft/file-upload/server/content/files/16124db793ef0e---95182420095.pdf
    • http://amuseonline.com/absite/userfiles/file/11597284670.pdf
    • http://partnerplus30.ru/images/fornews/files/59380454609.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_off0000cc6e.bin
ab8812dedb705ff31a0008c34bdbe5dbe98408334f00ee91bfcef5ae269da5b8
pdf-font-stream PDF embedded font (sfnt) at offset 0xCC6E 17740 bytes
font_01_sfnt_off0000fae6.bin
683a8dd990f01601b4cdec0ff2a99992bd3f9062680d2f513d8308e2b92f9d66
pdf-font-stream PDF embedded font (sfnt) at offset 0xFAE6 10908 bytes
font_02_sfnt_off00011404.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11404 16792 bytes