Malicious PDF — malware analysis report

Static analysis result for SHA-256 aa1ef74cb6931633…

MALICIOUS

PDF

87.0 KB Created: 2021-08-12 02:27:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e733cc0d4a2d0758aa717a0f32335542 SHA-1: 033efc9c4b65e9dc936374e4e90086b212965def SHA-256: aa1ef74cb6931633f3100f8315daf0863f777efd8e0d4e11f7cb6a75ad188426
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites. The ML classifier strongly indicated maliciousness, and the PDF_SEO_DISPOSABLE_LINK_FARM heuristic suggests a link farm intended for SEO manipulation or potentially distributing malware. No scripts were extracted, but the presence of external links on compromised infrastructure is a strong indicator of malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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://oiweld.com/wp-content/plugins/super-forms/uploads/php/files/db3c25ca462e2f039da4ed1b872ac241/vulagapedibulixijigu.pdf
    • https://jclifeschools.org/wp-content/plugins/super-forms/uploads/php/files/4c853f1304b63f02cda0bda932d3abf0/55465226249.pdf
    • http://verkoop-je-wagen.be/wp-content/plugins/formcraft/file-upload/server/content/files/160902f3f80e9e---26773114529.pdf
    • http://brandnewgoods.net/userfiles/file/lozomexesuxesidamuva.pdf
    • https://its-bulgaria.bg/files/file/rufaladefuw.pdf
    • http://call.ae/wp-content/plugins/formcraft/file-upload/server/content/files/1608fb4a60ea47---satibopi.pdf
    • http://bulk-supplies.com/userfiles/file/tukajikowetogekofikixufog.pdf
    • https://ahi.com.ua/wp-content/plugins/super-forms/uploads/php/files/f8e420b20b16cc89df58f857fd63ba8f/rutubeduzujapijideni.pdf
    • https://hinodanang.com/uploads/image/files/banewodukumudadomojumoxi.pdf
    • https://flexrocksrollovers.com/wp-content/plugins/super-forms/uploads/php/files/jp97d7r7dnon734mn6i1t17ef5/tagudirorojatu.pdf
    • http://unseenadventure.com/userfiles/file/11993516782.pdf
    • https://expeditions-travel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071ca76eba5f---43323943831.pdf
    • http://conservationenergy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b44ef69fa96---renemuzogipobitonexamola.pdf
    • https://amalighting.com/wp-content/plugins/super-forms/uploads/php/files/9f070afcc5cfdcb5447870ea23099fdf/54922037574.pdf
    • http://ophtalmic-overnight.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1609d1bc85f5da---wesinazuku.pdf
    • http://ytlcases.com/userfiles/file/36476029471.pdf
    • https://www.msolartop.cz/wp-content/plugins/formcraft/file-upload/server/content/files/160b6f50d88350---zetazabesenazas.pdf
    • http://maduraigarlandshop.com/userfiles/file/92115902195.pdf
    • https://kachhiproperties.com/wp-content/plugins/super-forms/uploads/php/files/7u4le5052i9bmt846vftm9med4/wukunuwitebejuduwirigijen.pdf
    • https://gaziemirkentkonseyi.com/upload/files/18967662546.pdf
    • http://strandedtattoo.net/file/71134079434.pdf
    • http://anadolumatbaa42.com/genelresimler/file/fimol.pdf
    • http://conwaychristian.org/wp-content/plugins/formcraft/file-upload/server/content/files/1609b4b0fc40b5---rizepiwepigob.pdf
    • https://embassyinvietnam.com/webroot/img/files/zakesara.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=previous+year+question+paper+class+10+cbse+maths
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ee30.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEE30 16792 bytes
font_01_sfnt_off00010647.bin
4c7ba39a501106aba6c3992a25e46dd6e74f25f885902f6a5e2972d583b8ffb2
pdf-font-stream PDF embedded font (sfnt) at offset 0x10647 11380 bytes
font_02_sfnt_off000120c8.bin
4c474c5036c1432f06621bc7d37fa10554f258b8505009e444bbdf7a2ca7b111
pdf-font-stream PDF embedded font (sfnt) at offset 0x120C8 17168 bytes