Malicious PDF — malware analysis report

Static analysis result for SHA-256 cf8c0bd71f09426b…

MALICIOUS

PDF

73.0 KB Created: 2021-04-28 17:42:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-23
MD5: 8fe569a3b8e1761d3ef840165548b76f SHA-1: d3e9a6de0b24f0281a98670e5f7f591a5054d759 SHA-256: cf8c0bd71f09426b2ef4c081003dadd58d3c4182e95c3e27efbe0beb9a1edd72
156 Risk Score

Malware Insights

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

This PDF was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous embedded URLs pointing to compromised CMS uploads, suggesting it's used to distribute further malicious content or phish users. The presence of external URI heuristics and the 'PDF_SEO_DISPOSABLE_LINK_FARM' firing confirm its role in directing users to potentially harmful external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://namastehealth.in/wp-content/plugins/super-forms/uploads/php/files/k96fphkr8g26m5hhcfo1tdlj6j/kuvusoduwam.pdf In PDF document text
    • https://prosegik.com/wp-content/plugins/super-forms/uploads/php/files/053d4792f442fdb49ac845f947da50aa/84592485616.pdfIn PDF document text
    • https://www.lowdoc-loans.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1606ef5ef4a794---xamiwazedomaromurokobi.pdfIn PDF document text
    • http://www.scmphotography.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16077793682dc0---vekokukafowikot.pdfIn PDF document text
    • http://english-island.pl/wp-content/plugins/super-forms/uploads/php/files/fdvtvr1ofq6amrvh2ab9u4a9g2/tugijekamavazutepek.pdfIn PDF document text
    • https://tcufroghouses.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608069699ee6c---rogalibetogibefokogi.pdfIn PDF document text
    • https://yidinfo.net/wp-content/plugins/super-forms/uploads/php/files/6uok1t1btsnenh6b5dpu332246/41402620792.pdfIn PDF document text
    • https://polinagerz.ru/wp-content/plugins/super-forms/uploads/php/files/cqjr57r1sa6eotc55g4u16kmst/75102075516.pdfIn PDF document text
    • https://www.stamfordtaxis.com/wp-content/plugins/super-forms/uploads/php/files/lqvbs2cm95rvlclmv4p0h8gd6h/44400710373.pdfIn PDF document text
    • http://lifemartrealestateconnect.com/wp-content/plugins/super-forms/uploads/php/files/9p6ck894hldo3lm1omac1cvfb2/doruwej.pdfIn PDF document text
    • https://fuchscars.com/wp-content/plugins/super-forms/uploads/php/files/008bc8a146cf8307a6a0080f6d3093cc/lipaxaxaxavanigumoxof.pdfIn PDF document text
    • https://www.saltriot.com/wp-content/plugins/super-forms/uploads/php/files/42f37c88405cb981908f944c1f7efc1f/10719409339.pdfIn PDF document text
    • https://www.hotwaterfactory.com.au/wp-content/plugins/super-forms/uploads/php/files/38ade011af1ff292427f86ac925b1b8c/judaruxamesofadudi.pdfIn PDF document text
    • https://veritiesinstitute.com/wp-content/plugins/super-forms/uploads/php/files/e11cc4ee24382be08c495988782f6a1c/14862273916.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=addition+and+subtraction+worksheets+for+class+3PDF link annotation
    • 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_off0000dfad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFAD 5560 bytes
SHA-256: ae42ca0b091c40a0d43ca2600f95741fcf41faf8f409df5a7421c0074cdb2ba5
font_01_sfnt_off0000f2a6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2A6 10596 bytes
SHA-256: cf69ff24142d8ffacd62c43afd082e30cf6992075638e42b2bb7ad8fae36e927