Malicious PDF — malware analysis report

Static analysis result for SHA-256 def780f8cc97ef7f…

MALICIOUS

PDF

108.4 KB Created: 2021-10-07 03:16:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 78b8b2b44522047a292e61a5b352d803 SHA-1: 54b8366ca9e6aed5bd802463b6cb1cd1cba5ad5a SHA-256: def780f8cc97ef7f1731ba6f2d9c21efa4e841199cfdb8ce22ea68c81a2252db
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm pointing to compromised CMS uploads and disposable hosting, suggesting it's used to distribute further malicious content or phish users. The embedded URLs, while numerous, are the primary indicators of compromise.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9967

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://castilloexterior.net/ckfinder/userfiles/files/siwelelewefobejulokaxipu.pdf In PDF document text
    • http://www.dreamstoreonline.es/ckfinder/userfiles/files/nemaxazezikamifenadadoro.pdfIn PDF document text
    • http://kingtonkatsu.com/uploads/files/38047937980.pdfIn PDF document text
    • https://turystycznapodkowa.pl/userfiles/file/lazusen.pdfIn PDF document text
    • https://commonlawhouse.in/userfiles/file/romep.pdfIn PDF document text
    • http://myxroad.net/upload/userfiles/file///vodafotabolete.pdfIn PDF document text
    • https://nmg.lv/img/uploads/files/dilisagonurufawukogobes.pdfIn PDF document text
    • https://buddingheights.org/wp-content/plugins/formcraft/file-upload/server/content/files/1614135b711084---67556643160.pdfIn PDF document text
    • https://griby.biz/ckfinder/userfiles/files/3554294714.pdfIn PDF document text
    • https://wamsconference.com/wp-content/plugins/super-forms/uploads/php/files/8110fd139f969ab76a483cd3cb06e6b1/vizurulororekeruwaravi.pdfIn PDF document text
    • http://villa-margherita.biz/userfiles/files/xuzipoditixak.pdfIn PDF document text
    • https://bunian-co.com/other_files/File/30105759154.pdfIn PDF document text
    • https://daotaolaixesontay.com/uploads/file/92635906613.pdfIn PDF document text
    • https://k-newsletter.com/ckupload/files/kagafatapefulidufir.pdfIn PDF document text
    • http://becro-plast.hr/wp-content/plugins/formcraft/file-upload/server/content/files/16134f612ecdbe---kedira.pdfIn PDF document text
    • http://www.saletime.gr/admin/fckfiles/file/70796402916.pdfIn PDF document text
    • http://ever0036.com/assets/uploads/ckedit/files/20211005185721.pdfIn PDF document text
    • http://www.malagatour.es/ckfinder/userfiles/files/22524259904.pdfIn PDF document text
    • http://atenngo.com/admin/sites/site/documents/35194894196.pdfIn PDF document text
    • http://cementfeet.com/userfiles/file/tipuwefukabo.pdfIn PDF document text
    • https://ohligschlaeger-berger.de/wp-content/plugins/formcraft/file-upload/server/content/files/1614615be3adb2---fapufomunavosofon.pdfIn PDF document text
    • http://neodentpetrosino.it/userfiles/files/24131889460.pdfIn PDF document text
    • https://best-label.com/upload/files/32467180275.pdfIn PDF document text
    • http://vecsecity.info/editor_up/molakopeginapawuketulol.pdfIn PDF document text
    • http://rydelko.eu/userfiles/file/89406278545.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=introduction+of+adsorptionPDF 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_off00013cb1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13CB1 10484 bytes
SHA-256: b1a02880a90c19a5f1bda315a2a94b804065de6c2216999d0a7b7475634c436d
font_01_sfnt_off000154a0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x154A0 20816 bytes
SHA-256: 94d219ca88d113b913f3b056014b53f9a3fd4bdb45ac45de15b5db5ee0d6543a
font_02_sfnt_off00018ba2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x18BA2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1