Malicious PDF — malware analysis report

Static analysis result for SHA-256 843b90992723de33…

MALICIOUS

PDF

71.8 KB Created: 2021-06-13 19:04:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-24
MD5: f18195689af3bb4b8e3ecc565a4f7bd5 SHA-1: a2b909480786750c4b5559331225560ae8992d3f SHA-256: 843b90992723de33e5e1ce63513de231e8d9d47f04751deb3cd1efcca351ca92
156 Risk Score

Malware Insights

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

This PDF file is identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It functions as a link farm, directing users to various URLs, many hosted on compromised WordPress sites or disposable domains, under the guise of MP3 downloads. The presence of embedded URIs and the structure suggest an attempt to redirect users to malicious content or further stages of an attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://chcial.ru/uplcv?utm_term=kalyana+mangala+isai+mp3+download PDF link annotation
    • https://gastrotest.co/ckfinder/userfiles/files/69088904497.pdfIn PDF document text
    • http://makaeximworld.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cbda9238b2---zazikararusaxavolafovexav.pdfIn PDF document text
    • https://mariapolis.net/ckfinder/userfiles/files/51832828330.pdfIn PDF document text
    • https://astoriareiki.com/wp-content/plugins/super-forms/uploads/php/files/ea78a5ff69326701fff95d72ac7fd044/5965644799.pdfIn PDF document text
    • https://inchirieriavioane.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1609bf7b52c3a9---8784644891.pdfIn PDF document text
    • https://www.frontierexim.com/wp-content/plugins/super-forms/uploads/php/files/177r6sa25jk6m8jghgg09nmki9/68327221943.pdfIn PDF document text
    • https://nowackleverkusen.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608116e9a215e---90368588501.pdfIn PDF document text
    • https://braviengenharia.com.br/wp-content/plugins/super-forms/uploads/php/files/k7ka72u6rrj2kb61m2ql8gbk1i/mibagenaserojefubadaro.pdfIn PDF document text
    • http://lifemartrealestateconnect.com/wp-content/plugins/super-forms/uploads/php/files/n422kcheape2a1apic0nvr5216/3673283068.pdfIn PDF document text
    • https://cffcommunications.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/1607233d47f7e7---nutenujujuferagexowe.pdfIn PDF document text
    • http://expresskaliski.info/file/57179556737.pdfIn PDF document text
    • https://e-lightingcontrols.com/wp-content/plugins/super-forms/uploads/php/files/bb6cf4a7b9d055ab8298b4983c50409b/15789336884.pdfIn PDF document text
    • https://www.azulejositurry.com/wp-content/plugins/super-forms/uploads/php/files/sarq9rr0punhgimji2pot9pb66/xivadalurula.pdfIn PDF document text
    • http://www.gesas.it/media/mailinglist/file/97971117577.pdfIn PDF document text
    • http://davidhammerstein.org/userfiles/file/tafuxeromarorisawe.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000cefb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCEFB 5100 bytes
SHA-256: 672e0057b3c06c2840371d236c7e8af64f2094bed1ebaad36cb3c622bd6e31b6
font_01_sfnt_off0000e04f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE04F 10452 bytes
SHA-256: 16c86732518dff4666e3718f980f9b5f43b216c17ea588c5ec62b330ad03f293
font_02_sfnt_off000103bd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103BD 4324 bytes
SHA-256: 1062cd8ddf90f4344fa193b395386d5669df1a952e5759311ca261a71931f361