Malicious PDF — malware analysis report

Static analysis result for SHA-256 91aa2c1d2afdd125…

MALICIOUS

PDF

85.4 KB Created: 2021-07-19 04:43:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 2ca730a470efcf03eaa8367460b26d8e SHA-1: b58c4115b6035b4248ce1ab4f8555d64dd5f23cf SHA-256: 91aa2c1d2afdd12539a73080e1a5c60a8f8e73f0b58a793ea1c9be26e4f0902f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous links, many of which point to compromised WordPress sites, suggesting a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution via these external links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 http://www.mkkdigital.pt/wp-content/plugins/formcraft/file-upload/server/content/files/1606ed2ddd0622---zozoxumikekefuv.pdf In PDF document text
    • https://www.oasipizza.it/wp-content/plugins/formcraft/file-upload/server/content/files/160b65e828deba---kinanakexufazu.pdfIn PDF document text
    • https://autoschiller.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608ba1aa24a8a---gapesejasuwovo.pdfIn PDF document text
    • https://daleplumbinginc.com/wp-content/plugins/super-forms/uploads/php/files/eb623d9c8b44bd3b264b6bea1a8147e2/zubofategubowadugav.pdfIn PDF document text
    • http://111-orte.de/testarea/cwsCMSlight/media/files/6646351331.pdfIn PDF document text
    • http://www.melloecastro.com/wp-content/plugins/formcraft/file-upload/server/content/files/16083b4986f077---85989831520.pdfIn PDF document text
    • http://pivotal-technologies.com/userfiles/file/tariwib.pdfIn PDF document text
    • https://hogies.com/includes/template/uploads/file/17032033796.pdfIn PDF document text
    • http://www.oschouston.com/osc/wp-content/plugins/formcraft/file-upload/server/content/files/1608bee2aefb6d---92355601663.pdfIn PDF document text
    • https://silga.ca/userfiles/file/vupuwem.pdfIn PDF document text
    • http://sherwoodonionfestival.com/ckfinder/userfiles/files/70116535699.pdfIn PDF document text
    • http://cesurmakina.com/userfiles/file/fowovix.pdfIn PDF document text
    • https://www.icslights.com/wp-content/plugins/super-forms/uploads/php/files/6a57bdf72dc86d95b8ace7bad31dcc00/zusaren.pdfIn PDF document text
    • https://amezdigital.com/wp-content/plugins/super-forms/uploads/php/files/eb0ef5e95f67219b703d1b43e80f234b/66764315826.pdfIn PDF document text
    • http://www.jcca.co.in/wp-content/plugins/formcraft/file-upload/server/content/files/1607aef3dbfc8e---59838241841.pdfIn PDF document text
    • http://bagumul.com/file_upload/spaw_upload/file/20210507032248.pdfIn PDF document text
    • http://www.majorisinvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607e2cc197425---60121465956.pdfIn PDF document text
    • https://maloneslandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a85f338c7db---wigapejerubu.pdfIn PDF document text
    • http://laiyi-art.com/userfiles/file/jejurotezoludigi.pdfIn PDF document text
    • https://www.bouldersudbury.org/wp-content/plugins/formcraft/file-upload/server/content/files/1609c2b2291143---75894039381.pdfIn PDF document text
    • http://for-rent-leuven.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a16fe88129c---94238341399.pdfIn PDF document text
    • https://tucarrorentacar.co/ckfinder/userfiles/files/22897185186.pdfIn PDF document text
    • https://gservicepz.com/wp-content/plugins/super-forms/uploads/php/files/ccdb422f43121c28b9d5d96f29c2c280/vevikija.pdfIn PDF document text
    • https://phase1acoustics.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071042682812---28787166476.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=monster+city+mod+apk+unlimited+money+and+gemsPDF 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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e963.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE963 17260 bytes
SHA-256: 59dfcfecaf748675c26b9dbc6498b9176b1779b0913bf458bfad66c70b9a8e3d
font_01_sfnt_off00011648.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11648 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012e5f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12E5F 11156 bytes
SHA-256: 63ce850a11757eb11b8be1ea98488b329984a4bcbaac198fea21a3f8ca9c238a