Malicious PDF — malware analysis report

Static analysis result for SHA-256 51f52c0b4704de79…

MALICIOUS

PDF

76.8 KB Created: 2021-06-26 22:41:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 6c3d51597d4fb73a377bb195e95e279d SHA-1: 1ef83e81099cab6969d2579f09dbe62f147b0d6b SHA-256: 51f52c0b4704de796ce7b7ce0eef1bc0681bfad6f29740df548ea97da3a4756a
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to compromised WordPress sites acting as a link farm. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. The embedded JavaScript suggests an attempt to execute code within the PDF viewer.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9919

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://www.taxikladis.gr/wp-content/plugins/formcraft/file-upload/server/content/files/16078d719076b6---66549593538.pdf
    • https://archltginc.com/wp-content/plugins/super-forms/uploads/php/files/f60b27908762c56c5bd81ba53ab1879e/kexuxadiwesudapatosabo.pdf
    • http://longbienco.com/js/ckfinder/userfiles/files/dugal.pdf
    • https://condominiovillage.com/userfiles/file/68403692337.pdf
    • http://maszyny.pl/userfiles/file/juvijinifilirudapimufos.pdf
    • http://sacoorhealth.pt/site/upload/file/fiwetuguris.pdf
    • https://www.truesdalepainting.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a4be9768633---68277524224.pdf
    • http://www.gametimecatering.com/wp-content/plugins/formcraft/file-upload/server/content/files/160778ec924c97---sapadatulirorena.pdf
    • http://emotionpicturesfestival.gr/userfiles/file/suvunitojizadevigunadenev.pdf
    • https://nobleanimalsanctuary.org/wp-content/plugins/super-forms/uploads/php/files/tmp/vodagofor.pdf
    • https://gservicepz.com/wp-content/plugins/super-forms/uploads/php/files/96b50165d98d368f8bc51be5b19ab3d3/47465713008.pdf
    • https://newat.ru/wp-content/plugins/super-forms/uploads/php/files/a1ebad092e61981694ad50d75ef67699/munivegotibofab.pdf
    • https://stagerightstaging.com/wp-content/plugins/super-forms/uploads/php/files/9075c7ed253a8f3d6cb22d407bc103c4/vozedosijovexewisogorena.pdf
    • http://springswellness.net/wp-content/plugins/formcraft/file-upload/server/content/files/160c125f69c8cb---1539410094.pdf
    • https://alllegaltask.com/wp-content/plugins/super-forms/uploads/php/files/qcsnck2qfrqepq0iijs99i0piv/xibetosidu.pdf
    • https://www.cir.cloud/wp-content/plugins/formcraft/file-upload/server/content/files/16073c4787a1f2---mikozivilaremijijopap.pdf
    • http://www.ponderosafestival.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d5db566266---53620642579.pdf
    • http://intechsol.kz/wp-content/plugins/formcraft/file-upload/server/content/files/160773aac0d048---29893356162.pdf
    • http://work4shop.cz/userfiles/file/bopujirut.pdf
    • http://hocikto.info/userfiles/file/41735554770.pdf
    • https://www.histoiresdegroupes.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077eae2a6fdb---ziwex.pdf
    • https://xn--i1aam8cb.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/fe92edf61a9d939b11e13eab90bfe635/rinatuvakubokakuwana.pdf
    • http://baschin-heizung.com/meineBilderAlbertGrundschule/file/jugesikezudofilidip.pdf
    • http://helloshoppingnepal.com/userfiles/file/38144193039.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=how+to+pronounce+reservoir
    • 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000bdd9.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xBDD9 16792 bytes
font_01_sfnt_off0000d5e6.bin
9628d52b4563b97264a928434ed8fe35301e83bea82525a53cf72cd3f9c7379d
pdf-font-stream PDF embedded font (sfnt) at offset 0xD5E6 3552 bytes
font_02_sfnt_off0000e3b8.bin
2238430e423a6d83b617e5719214343d3e2e03a18f103b0e3ee4a1e09740be0a
pdf-font-stream PDF embedded font (sfnt) at offset 0xE3B8 10400 bytes
font_03_sfnt_off0000fb71.bin
652427d77869969e456bcaf050794f95bb84599bb48d6034602431dcb2886e90
pdf-font-stream PDF embedded font (sfnt) at offset 0xFB71 16112 bytes