Malicious PDF — malware analysis report

Static analysis result for SHA-256 36e0b4688bcc16e8…

MALICIOUS

PDF

73.6 KB Created: 2021-05-27 20:10:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-16
MD5: ef956c2b5f879d8a2af67e6364276280 SHA-1: a5f268062d8e31fb07a29b1f01992d99930d4675 SHA-256: 36e0b4688bcc16e8389bbacd7779ffbdbd637e387740cd7d7abf45464f69b832
156 Risk Score

Malware Insights

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

The PDF contains multiple links to external websites, many of which are hosted on compromised WordPress installations or disposable domains, suggesting a link farm designed to distribute malicious content. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware delivery. No scripts were extracted, but the PDF structure itself facilitates the redirection.

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://synerhu.ru/uplcv?utm_term=common+english+phrases+for+conversation+pdf PDF link annotation
    • https://www.sblending.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1606d173cb8853---41166899090.pdfIn PDF document text
    • https://srp-galabau-rostock.de/wp-content/plugins/super-forms/uploads/php/files/5fhnstfdd91bbc5pja5lgprjt7/wavivojedakage.pdfIn PDF document text
    • https://www.sudburyhighspeedinternet.ca/wp-content/plugins/super-forms/uploads/php/files/5740ff3df3b614c0e7ee7b30657fee6e/ritutirukiwekavisiwevozi.pdfIn PDF document text
    • https://www.schroedersales.com/wp-content/plugins/super-forms/uploads/php/files/4af5cc6436a3606481816c5626bee39d/80150526908.pdfIn PDF document text
    • https://qamarapps.com/wp-content/plugins/formcraft/file-upload/server/content/files/160947be2ad587---23489629288.pdfIn PDF document text
    • https://drvishweshwari.in/userfiles/file/66740129933.pdfIn PDF document text
    • https://popcouncilinstitute.org/wp-content/plugins/super-forms/uploads/php/files/4462e29440a81246b0d6bfd28db6627c/guwipirefusufup.pdfIn PDF document text
    • https://gresathouse.com/wp-content/plugins/super-forms/uploads/php/files/7462579292adff213332b84b9d9256e9/68992459643.pdfIn PDF document text
    • https://spencershaulageltd.co.uk/wp-content/plugins/super-forms/uploads/php/files/a3f8741ad376abcec25d048823faac07/91110094165.pdfIn PDF document text
    • http://symbioticlifetech.org/attfile/fckimg/file/%5C/2021051034759_24024101.pdfIn PDF document text
    • http://www.predoisiasociatii.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160a351275f72e---togurisesepip.pdfIn PDF document text
    • https://journeypeople.cc/wp-content/plugins/super-forms/uploads/php/files/f8310f280200b5032a8f9bacfeb67daa/49318102294.pdfIn PDF document text
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/aaov9nl7udpt8ek07sl847cjb0/59241549800.pdfIn PDF document text
    • https://prikolnaya.com/wp-content/plugins/super-forms/uploads/php/files/113db38befeee6866deabb36f2c20ece/2632906634.pdfIn PDF document text
    • https://jjmassociates.com/wp-content/plugins/super-forms/uploads/php/files/d26f87b35f161cfb6cf264bdd28af5e1/gabenax.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d9d5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9D5 5532 bytes
SHA-256: 2b9184b67567b40d5d8be7362cd803d920a46819e146ecfcec497f04772203b8
font_01_sfnt_off0000ec7a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC7A 1800 bytes
SHA-256: 51ebeec29509b87aa858d500e37ac8853184703d07d1f913ce36d8e1dc7764c0
font_02_sfnt_off0000f508.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF508 10404 bytes
SHA-256: 89a54f27a914cb40c36a5e65d57b39c9a84b518b19f1c4e8a7cada251930333d