Malicious PDF — malware analysis report

Static analysis result for SHA-256 3a4e71786e935dd8…

MALICIOUS

PDF

75.5 KB Created: 2021-06-23 07:01:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-16
MD5: 4385cde9b6e729fbe0c1227258704881 SHA-1: adc54976f2a70ae310055b69adc02d178a2dcb8c SHA-256: 3a4e71786e935dd8197560db6b661e0949260af44111bde9ed177770f83b0734
104 Risk Score

Malware Insights

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

The ML classifier strongly indicated maliciousness, and multiple heuristics identified the PDF as a link farm pointing to compromised WordPress sites and disposable hosting. The document body, though heavily obfuscated, contains text related to trivia questions and application details, suggesting a lure. The presence of numerous external URIs indicates the document's primary purpose is to redirect the user to potentially malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • 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.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • 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://crysiq.ru/uplcv?utm_term=everyday+trivia+questions+and+answers PDF link annotation
    • http://ggmtc.net/userfiles/files/sanonadiju.pdfIn PDF document text
    • https://k9-warrior.com/wp-content/plugins/super-forms/uploads/php/files/tg8kqubn0cjstfg9ecdacm9l79/94478121967.pdfIn PDF document text
    • https://rajaunited.com/contents//files/65815645041.pdfIn PDF document text
    • https://teplitsyoptom.ru/wp-content/plugins/super-forms/uploads/php/files/5f11f0f2ff83545b834fc8a29ccadc7f/perofiwemukutilumusopu.pdfIn PDF document text
    • http://snookerfootball.eu/wp-content/plugins/formcraft/file-upload/server/content/files/16072e3bc7629c---97919349990.pdfIn PDF document text
    • https://www.blackandwhite-salon.com/wp-content/plugins/super-forms/uploads/php/files/483d3e7a70a6ef9821952c4a94a2807a/jemexavevefa.pdfIn PDF document text
    • https://gearforfree.com/wp-content/plugins/super-forms/uploads/php/files/abi7qgup13gq4prit8lenkkdca/nenarokaj.pdfIn PDF document text
    • https://xn----9sbccjdbca7cyaieg1a3j.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/1d6af11c016e62d8a62874e7fdaf2b13/filazawiwivager.pdfIn PDF document text
    • http://aftckwt.com/uploads/file/vozas.pdfIn PDF document text
    • https://robinio.de/wp-content/plugins/super-forms/uploads/php/files/ts0cbctc89ldcq8ojbcpft805t/24521680855.pdfIn PDF document text
    • http://clearlakesd.org/wp-content/plugins/formcraft/file-upload/server/content/files/160833c4634cb8---4194771712.pdfIn PDF document text
    • https://xn--nmqu14inmf.com/upload/files/robofijebavufosunosozawov.pdfIn PDF document text
    • http://saintthomasmonrovia.org/clients/a/a7/a774d5b45fc75aba9c6fcf07501e1e58/File/gifipaxirevubabumazezipa.pdfIn PDF document text
    • https://www.chartsunlimited.com.ph/wp-content/plugins/formcraft/file-upload/server/content/files/1609de44e6caea---72821772429.pdfIn PDF document text
    • http://www.fliesen-brill.de/wp-content/plugins/formcraft/file-upload/server/content/files/16097044368084---dubovomere.pdfIn PDF document text
    • https://beytarimcilik.com/admin/editor_resim/file/poloki.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_off0000e78a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE78A 5124 bytes
SHA-256: 1cab1574f0b03c273275a11ce5624d6cc201de4330a80c5943c0ccb1c4afca8e
font_01_sfnt_off0000f91e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF91E 11864 bytes
SHA-256: 31e70bb674e113eec8e68e7ccc8560d396c39c515b885a86251ee778fb5c370d