Malicious PDF — malware analysis report

Static analysis result for SHA-256 9c3590224fa5fea8…

MALICIOUS

PDF

102.8 KB Created: 2021-06-10 01:59:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-24
MD5: 5a9809a16e9e92f3e352e1c16d77d167 SHA-1: 3e37b636b20ac6fcf115f18da714abd6fe459833 SHA-256: 9c3590224fa5fea8b9182bcb58f32e71eb40f7b8442aac17068eab1b1292dd43
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF document contains numerous links to compromised WordPress sites and disposable hosting, masquerading as a download for 'Gltools alternative no root'. The ML classifier strongly indicates malicious intent, likely to serve a second-stage payload. No scripts were extracted, but the link farm and compromised CMS uploads suggest a distribution mechanism for malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://laborke.ru/uplcv?utm_term=gltools+alternative+no+root PDF link annotation
    • http://ztkammer.at/uploads/file/51930773373.pdfIn PDF document text
    • http://www.morenoroofing.com/wp-content/plugins/formcraft/file-upload/server/content/files/160819ff6e43a9---2379089275.pdfIn PDF document text
    • https://rescue.bg/wp-content/plugins/formcraft/file-upload/server/content/files/160bcea875c79e---xobuge.pdfIn PDF document text
    • http://alacarte-design.de/userfiles/file/12631683135.pdfIn PDF document text
    • https://braviengenharia.com.br/wp-content/plugins/super-forms/uploads/php/files/fd36f40lou4oj5qg4evva3dj2k/74220623911.pdfIn PDF document text
    • https://sakitonus.ru/wp-content/plugins/super-forms/uploads/php/files/d43f5c34dbe819782d32b9b34d38ba1c/kevakefolu.pdfIn PDF document text
    • http://windcampus.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a65d33e6014---zejus.pdfIn PDF document text
    • http://www.appsolutely.sg/wp-content/plugins/formcraft/file-upload/server/content/files/1609380aac6815---71514208063.pdfIn PDF document text
    • https://engravestone.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087167927832---482628484.pdfIn PDF document text
    • https://www.heracles-hotel.eu/wp-content/plugins/super-forms/uploads/php/files/5bellg5q0ouehgld305g4kjrar/xusutuvuju.pdfIn PDF document text
    • https://nobleanimalsanctuary.org/wp-content/plugins/super-forms/uploads/php/files/tmp/96430949477.pdfIn PDF document text
    • http://www.leesii.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070064704115---gewadipefuganopup.pdfIn PDF document text
    • http://allaboutdowney.com/userimages/sifilolimalosanubawefizak.pdfIn PDF document text
    • https://cffcommunications.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/1606da267ec15d---noxudodusidujekix.pdfIn PDF document text
    • https://www.llgnjinc.com/wp-content/plugins/super-forms/uploads/php/files/426fa0f2a9a004524fd42fe56178a57d/gelinimosoxaguwitixeti.pdfIn PDF document text
    • http://anhuicrew.com/upload_fck/file/2021-5-19/20210519122401803664.pdfIn PDF document text
    • http://nessium.fr/userfiles/file/xifakuwopitasirol.pdfIn PDF document text
    • https://tecsal.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b9bd5c5318d---bazizagusidaxuw.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000152bd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x152BD 4768 bytes
SHA-256: 5c97e16e26d240ca9bf5184c03eb9bcc5d7050b2254d30bf96e4cfe3641bacdc
font_01_sfnt_off0001630b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1630B 13036 bytes
SHA-256: 0cd2589296b4cb68a6aad23ebee51ebf469f916042b3487c07fbbab46cb4ec6e