Malicious PDF — malware analysis report

Static analysis result for SHA-256 87c9b2b0e4bcaaf3…

MALICIOUS

PDF

79.2 KB Created: 2021-09-18 15:25:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 0690a4429ddf4a367479358844628cfe SHA-1: c9b94fdd21e061759accc9792746269d8d928a6d SHA-256: 87c9b2b0e4bcaaf3fc0d3a0edadcdc7bdf159d2711c019e7babdf1967a5f669d
156 Risk Score

Malware Insights

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

The PDF document contains numerous embedded URLs that point to compromised websites and link farms, indicating a phishing or content distribution scheme. The ML classifier and ClamAV detection strongly suggest malicious intent, likely to lure users to malicious sites. No scripts were extracted, but the structure and URL patterns are indicative of a link farm used for initial access.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://huntic.ru/uplcv?utm_term=pendant+of+wound+closure PDF link annotation
    • http://zussobrance.sk/grafika/dokumenty/10080118856.pdfIn PDF document text
    • http://55pluscommunityspecialist.com/userfiles/files/puxogabakaxoxuzagiz.pdfIn PDF document text
    • https://akconta.com/uploads/files/51624241511.pdfIn PDF document text
    • http://ayhancevik.com/images_upload/files/79160501268.pdfIn PDF document text
    • http://triumphtoday.org/wp-content/plugins/formcraft/file-upload/server/content/files/16133d7dc02d4f---puxumozoxokakeledotozun.pdfIn PDF document text
    • https://www.hadlowsecurityshutters.com/wp-content/plugins/super-forms/uploads/php/files/f7dd3a055a64bfe0a425259d15200f94/nitedepevejisuzalikogiz.pdfIn PDF document text
    • http://unipell.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161428c2029dcd---61200789258.pdfIn PDF document text
    • https://www.americanapi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614414b4ad4e2---lubixewigapudefolube.pdfIn PDF document text
    • http://tt-ural.su/admin/ckfinder/userfiles/files/vodulepefibufawo.pdfIn PDF document text
    • https://szpital-sulecin.pl/images/fckfiles/file/65398753265.pdfIn PDF document text
    • http://karthikeyanjayaram.com/userfiles/file/navan.pdfIn PDF document text
    • https://littleedupark.com/ckfinder/userfiles/files/48608655988.pdfIn PDF document text
    • https://rosedreamholidayhomes.com/ckfinder/userfiles/files/81803573586.pdfIn PDF document text
    • https://cli-kh.com/uploads/files/202109102144346665.pdfIn PDF document text
    • http://kanoonkaraj.ir/dbmanager/filebank/htmlgallery/file///sojoxafozolotuwupaw.pdfIn PDF document text
    • http://gadkowski.pl/repository/filemanager/file/pekagefikeborenuxaguw.pdfIn PDF document text
    • http://www.siscard.com/wp-content/plugins/formcraft/file-upload/server/content/files/16144334770edf---78016663564.pdfIn PDF document text
    • http://xn--b1amishc2fb.xn--p1ai/ckfinder/userfiles/files/28775333905.pdfIn PDF document text
    • http://mirembeestate.co.ug/wp-content/plugins/formcraft/file-upload/server/content/files/161428b0e53848---63795289733.pdfIn PDF document text
    • https://sproname.com/files/userfiles/files/fojekake.pdfIn PDF document text
    • http://steelfurniturecn.com/d/files/21369747357.pdfIn PDF document text
    • http://chinhsuasolieu.com/media/files/muvizagudisunakuxabowe.pdfIn PDF document text
    • http://vdgairconditioning.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16144b9c570935---judipozifiwupujepigipurop.pdfIn PDF document text
    • https://www.advids.co/wp-content/plugins/formcraft/file-upload/server/content/files/1613d125081842---dirifavuruzepusu.pdfIn PDF document text
    • 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_off0000d192.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD192 17172 bytes
SHA-256: 012127e91d9955c61d7e676c32fba2324372673b1d51d5536353f4bbfe90b99f
font_01_sfnt_off0000fdf9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDF9 10564 bytes
SHA-256: 039fa1ee1764a5dd22aa609d5573c9b7f9b82695c5e2bb907f469628d04bed5d
font_02_sfnt_off00011656.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11656 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1