Malicious PDF — malware analysis report

Static analysis result for SHA-256 10c0ecacabd6d596…

MALICIOUS

PDF

86.2 KB Created: 2021-07-15 11:28:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 7fb4b182ef28b564ae7c62b9571f3f70 SHA-1: 9805ad3ccdb1f24ef30c9053677dbf02bd910077 SHA-256: 10c0ecacabd6d59604c96ab4b5a87c73a42869c87ae7b1995bcca05e7f16d065
96 Risk Score

Malware Insights

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

The PDF file contains a link farm with numerous URLs pointing to compromised WordPress sites, which in turn host other PDF files. This suggests a tactic to manipulate search engine results or distribute malicious content through a chain of compromised resources. The ML classifier strongly indicated maliciousness, supporting the assessment of a malicious link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

Heuristics 5

  • 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://pistant.ru/uplcv?utm_term=what+colour+goes+with+lilac PDF link annotation
    • https://ecomassage.pt/wp-content/plugins/super-forms/uploads/php/files/bt2okk9nhbtv6evim69u1su0tf/96629092576.pdfIn PDF document text
    • https://lorenzonimmigrationlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a5728928873---sobifilubilokokenadabun.pdfIn PDF document text
    • http://americansemitruckparts.com/d/files/52180644525.pdfIn PDF document text
    • http://kulturazebrak.cz/userfiles/14457327326.pdfIn PDF document text
    • https://borderpak.com/wp-content/plugins/super-forms/uploads/php/files/d43d9eacbc12dc6ca51ecf5d6bd2aca4/mefawerefiwuxufujuxi.pdfIn PDF document text
    • https://cncunse.com/d/files/90128427879.pdfIn PDF document text
    • https://www.hed-endo.hr/wp-content/plugins/formcraft/file-upload/server/content/files/1607033d92db07---95469192520.pdfIn PDF document text
    • http://hillcountryawningsandsunscreens.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075b0327bcfe---jetididesape.pdfIn PDF document text
    • https://agrotehholding.ru/wp-content/plugins/super-forms/uploads/php/files/3644779ab31e578052d1a3f95db8196e/wusevetalozimunemadal.pdfIn PDF document text
    • http://modelkyujin.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aeb089f372e---sowefu.pdfIn PDF document text
    • http://math-talk.kr/wp-content/plugins/super-forms/uploads/php/files/cof5eubqv7q02hbrdil8s0ni9s/zisolesuziloromejo.pdfIn PDF document text
    • http://www.annaleehuber.com/content_files/file/fojonazovapozid.pdfIn PDF document text
    • http://riggi.ru/userfiles/file/totigixibejubin.pdfIn PDF document text
    • https://thewentworthco.com/wp-content/plugins/super-forms/uploads/php/files/pih13a5su8fcnvh8kjebpcl2e8/wibapewidir.pdfIn PDF document text
    • http://curry-box-deluxe.de/userfiles/file/bopixanezigubak.pdfIn PDF document text
    • https://alphaveneers.co.uk/wp-content/plugins/super-forms/uploads/php/files/38d59917e935beb71ed71e0bfbea6870/6261687992.pdfIn PDF document text
    • http://www.chicagoalphas.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608a69aea67fd---21900714567.pdfIn PDF document text
    • https://2greenchicks.com/wp-content/plugins/super-forms/uploads/php/files/00152e36544a167d585a7db50deac39c/gamekoluferowilepabotuf.pdfIn PDF document text
    • http://www.psstrecno.sk/wp-content/plugins/formcraft/file-upload/server/content/files/160a96d69e2eca---14123052403.pdfIn PDF document text
    • http://facilitymanagementassociates.com/survey/userfiles/files/sapugijapuxabaridime.pdfIn PDF document text
    • https://dentinale.eu/wp-content/plugins/super-forms/uploads/php/files/cf5fd83bfd8995ae247a33c3d297fa1f/vupamo.pdfIn PDF document text
    • http://perlawarmii.pl/userfiles/file/95741722244.pdfIn PDF document text
    • http://smolensk-bakaleya.ru/userfiles/file/guzezuxax.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_off0000ef87.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF87 10584 bytes
SHA-256: ee8d4c52c23b5e83f4755586b623cd7b44e2ce94c5cec912b08db7338e8aec91
font_01_sfnt_off000107f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107F6 16756 bytes
SHA-256: c7c0ec7c0bb95a05a367e31999218aa3e7a42af99d6fa1cc0f83cdea58cac0ee
font_02_sfnt_off00013367.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13367 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1