Malicious PDF — malware analysis report

Static analysis result for SHA-256 f531354f4bc1437a…

MALICIOUS

PDF

76.5 KB Created: 2021-09-07 04:27:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: de826182e4a227a8a2831c4ad80d6dd9 SHA-1: 7f95300bd19864a96869f22f0a6a1a647409bbd8 SHA-256: f531354f4bc1437a66ba0185cf6156f0bd61e16dd435b23336eb464c7325720f
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier. It contains embedded JavaScript and a large number of external URIs, many of which point to compromised WordPress sites acting as a link farm. The primary purpose appears to be directing users to potentially malicious or phishing content through these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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://mkting.com.co/wp-content/plugins/super-forms/uploads/php/files/0e3b29d6e0e69dbbab3b64589ff72895/81733036180.pdf In PDF document text
    • http://hk-dcc.com/wp-content/plugins/super-forms/uploads/php/files/80k8bmfnt3f2kc87fskrbhr053/tutulofoz.pdfIn PDF document text
    • http://jameshamiltondds.com/clients/6/6c/6cc67b5d90347a591bf4e9c0b97a5143/File/naxigomu.pdfIn PDF document text
    • https://pinotcar.com/wp-content/plugins/super-forms/uploads/php/files/d33e6420febff87ab2c41e4d917979fa/faxenixulevidazapuju.pdfIn PDF document text
    • http://www.morenoroofing.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d84e9e169e0---jogevosuserofegag.pdfIn PDF document text
    • http://ahsaipu.com/v15/Upload/file/202151451182983.pdfIn PDF document text
    • http://tentimesneedlehill.com/UPFILE/userfiles/files/81318461621.pdfIn PDF document text
    • https://connect.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/462d35510f1023a316ea1ea11e1d0262/todepetamidubuwipodufetar.pdfIn PDF document text
    • http://bouwbedrijfansing.nl/userfiles/file/63352638644.pdfIn PDF document text
    • https://www.mixedclass.com.au/wp-content/plugins/super-forms/uploads/php/files/mms78e32fabts2le10tfgqm315/pobegoxesopejon.pdfIn PDF document text
    • http://deurwater.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c582868a819---zanigavuxu.pdfIn PDF document text
    • http://www.hro.ait.ac.th/js/ckfinder/userfiles/files/69928216758.pdfIn PDF document text
    • https://www.formwork.co.uk/wp-content/plugins/super-forms/uploads/php/files/v2o4aljhc22mhkgk51antb9vkl/litelijumi.pdfIn PDF document text
    • https://smartmedia.ro/app/webroot/files/userfiles/files/timakijapawakolomusaligup.pdfIn PDF document text
    • https://total-sport.pl/img/upload/files/kaveja.pdfIn PDF document text
    • http://festivaldeliteraturadepereira.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bf03fd7eb49---dipediwatevetuvebanap.pdfIn PDF document text
    • http://drvision.org/wp-content/plugins/formcraft/file-upload/server/content/files/160be10a71457d---mepumetenizogujetixurej.pdfIn PDF document text
    • http://vtracauto.com/wp-content/plugins/formcraft/file-upload/server/content/files/16094201d2cdbb---70074298754.pdfIn PDF document text
    • http://www.patricktennis.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160c885f16e9e5---7476742366.pdfIn PDF document text
    • http://recamonde.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609443d8b252b---20517100752.pdfIn PDF document text
    • http://kondicionery-fryazino.ru/upload_picture/file/fagaloxujejutijen.pdfIn PDF document text
    • http://audiomaster.se/wp-content/plugins/formcraft/file-upload/server/content/files/1607c5e35cbfed---23959440281.pdfIn PDF document text
    • http://live-lessons.net/lcj/web/uploads/assets/file/lokukeb.pdfIn PDF document text
    • http://grafiport.com/userfiles/file/28858094247.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=gm+4l60e+transmission+rebuild+manualPDF 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_off0000c563.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC563 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000dd7a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD7A 11056 bytes
SHA-256: d44d78285f3d9452e0a5807a01c1aa43b3f1d86b7194ff153bab974b478ffc76
font_02_sfnt_off0000f733.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF733 17500 bytes
SHA-256: fb77e76718f0d84d2e7ef83bf07bc9172decb10e7a455f8545687e96476cc330