Malicious PDF — malware analysis report

Static analysis result for SHA-256 9f4876bac17613c9…

MALICIOUS

PDF

83.0 KB Created: 2021-09-01 05:51:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: c0bd04f41a30ffc2e27422bc2afa8c63 SHA-1: a4700d55568fe29cbd46b335f114de5c536ef2a1 SHA-256: 9f4876bac17613c9fe24d12116754ced63cd92caaaadd64df497a7924cf059c5
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript and a large number of external URIs, many of which point to compromised WordPress sites or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent. The embedded JavaScript likely facilitates the redirection to these malicious sites, which are structured as a link farm to obscure the ultimate destination.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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://drmiamiconnect.com/wp-content/plugins/super-forms/uploads/php/files/929dd2d73f228fa6414a7e6fbcbd07ef/dabesosajo.pdf In PDF document text
    • http://eventcompany.org/clients/e/e3/e30ef11cf4efe639fe6592aa37b9cb94/File/nemakanutuxap.pdfIn PDF document text
    • https://frennphotography.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e394f0eccc5---15357486648.pdfIn PDF document text
    • https://proartgaleria.hu/files/files/ronom.pdfIn PDF document text
    • https://drivingschoolofnorthtexas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160792c30774fe---jazaf.pdfIn PDF document text
    • https://advantagelic.com/singhania/downloads/file/zudovinimesuvikuxagawe.pdfIn PDF document text
    • http://limoride.net/gallery/file/296399768.pdfIn PDF document text
    • http://hgb.se/filer/file/zudinajipekowojebifopip.pdfIn PDF document text
    • http://luvnchrlysenglishtoys.com/clients/861429/File/67504841588.pdfIn PDF document text
    • http://nassagroup.org/app/webroot/js/ckfinder/userfiles/files/61396604548.pdfIn PDF document text
    • http://edgecs.net/documents/52087302746.pdfIn PDF document text
    • http://exactblue.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608978942fb82---94964845669.pdfIn PDF document text
    • https://michaels-limo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ab5b224cb30---73321862432.pdfIn PDF document text
    • https://bf-pomosch.ru/wp-content/plugins/super-forms/uploads/php/files/vecgv6cas0tcvofhcavraq3le3/damijarilifutag.pdfIn PDF document text
    • http://sanxuatbanthinghiem.org/app/webroot/uploads/files/ratidegesav.pdfIn PDF document text
    • http://principessavencanice.com/wp-content/plugins/formcraft/file-upload/server/content/files/16100ac68350dd---lijelagotaj.pdfIn PDF document text
    • http://cp-1.ru/userfiles/files/36965177400.pdfIn PDF document text
    • http://nextgt.eu/uploads/file/3895826366.pdfIn PDF document text
    • http://www.timtransportes.com/home/wp-content/plugins/formcraft/file-upload/server/content/files/160c40ef79315c---vedevukak.pdfIn PDF document text
    • https://lightsourceindiana.com/wp-content/plugins/super-forms/uploads/php/files/1bbad7653ca37b8ece357e3b152ccaad/busime.pdfIn PDF document text
    • http://munnarinfo.in/userfiles/file/tuguwebowuderos.pdfIn PDF document text
    • https://dentinale.eu/wp-content/plugins/super-forms/uploads/php/files/73f98a9336eb6e3d90b0f9a6a2429a09/82136968275.pdfIn PDF document text
    • http://beamstraffic.ae/amb/userfiles/file/3899198186.pdfIn PDF document text
    • http://khanaphatgroup.com/UserFiles/file/52327740352.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=first+conditional+ejemplosPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d975.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD975 10780 bytes
SHA-256: d6b6f3168e78c2ee210f595d088f434d71af1096b4b917e22533b8e9eba91685
font_01_sfnt_off0000f237.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF237 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010a49.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A49 19408 bytes
SHA-256: 1a2a154b8e2da0ffcd8b5d3235219f5fde310dd965adeb18c718d0e10398ea37