Malicious PDF — malware analysis report

Static analysis result for SHA-256 c53a6cc921a452c4…

MALICIOUS

PDF

89.8 KB Created: 2021-09-03 23:23:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 6a6e663590b7c03b126f64b603e7a0f1 SHA-1: e57fc7c2c3b65ff8087d4fd3d379d66791756428 SHA-256: c53a6cc921a452c410be6fe66b97e355c2c0f11a3abc7c9f135be2447a27ab30
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. It contains numerous external URLs, many pointing to compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users. The presence of embedded URLs and the overall structure indicate a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9913

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 https://oniceh.ru/uplcv?utm_term=ejercicios+de+proporcionalidad+directa+e+inversa+resueltos+pdf+2+eso PDF link annotation
    • http://devveb.net/userfiles/file/14996208931.pdfIn PDF document text
    • https://growmytruck.com/wp-content/plugins/super-forms/uploads/php/files/2336c84c209dae16692d9670be991bf0/20886177616.pdfIn PDF document text
    • http://vstarmp.cn/upload/files/20210710_142116.pdfIn PDF document text
    • https://pabausa.org/wp-content/plugins/formcraft/file-upload/server/content/files/160d759f45faa6---97981897170.pdfIn PDF document text
    • https://gservicepz.com/wp-content/plugins/super-forms/uploads/php/files/dbc92ab46eb28811b63fb31e5f13497c/53433096715.pdfIn PDF document text
    • http://www.jhannahs.com/wp-content/plugins/formcraft/file-upload/server/content/files/160972b5ce42b3---gewodu.pdfIn PDF document text
    • http://nfraccon.org/userfiles/file/giwokuriwogalijilesu.pdfIn PDF document text
    • http://sakaryakasaplarodasi.org/userfiles/file/sadetunaguzomenelo.pdfIn PDF document text
    • http://koreanhotpot.com/uploads/files/nitejifavadizemizonikiri.pdfIn PDF document text
    • https://www.icslights.com/wp-content/plugins/super-forms/uploads/php/files/0719346bc4653abd524b31da8242d880/7213114635.pdfIn PDF document text
    • https://hoffmanowska.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160750100a15f1---91769285082.pdfIn PDF document text
    • http://hollywoodterrace.org/clients/863344/File/84277282454.pdfIn PDF document text
    • http://consulcongress.it/uploads/assets/file/75666653109.pdfIn PDF document text
    • http://mail.teleserviciomalaga.com/ckfinder/userfiles/files/54370086537.pdfIn PDF document text
    • https://roadtoring.com/wp-content/plugins/super-forms/uploads/php/files/781dde33a887e9f66fa4827e56b582e7/7462319790.pdfIn PDF document text
    • http://kaus21.com/userData/board/file/zefitaran.pdfIn PDF document text
    • https://www.aironface.com/wp-content/plugins/super-forms/uploads/php/files/df1fcd825ead5bd9ca01bb576f83f15f/fadowewitevi.pdfIn PDF document text
    • http://ciccioinpentola.com/userfiles/files/36057815671.pdfIn PDF document text
    • http://twtipa.com/upfile/files/2021/08/23/17796065314.pdfIn PDF document text
    • https://amenagementsoleil.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c6880132885---10453773766.pdfIn PDF document text
    • https://alrashed-alsaleh.com/userfiles/files/1965843508.pdfIn PDF document text
    • https://jmtours.co/aym_image/files/31028710719.pdfIn PDF document text
    • https://controlcert.se/wp-content/plugins/formcraft/file-upload/server/content/files/160a40fc57613f---korilat.pdfIn PDF document text
    • https://www.simcoerecovery.net/wp-content/plugins/super-forms/uploads/php/files/2d2umaaauia4jeo23jchllpdpd/wujuwijixedokuvexiri.pdfIn PDF document text
    • http://barrospizzadb.com/uploads/files/1005148318.pdfIn PDF document text
    • http://aarogyamedico.com/userfiles/file/60344202434.pdfIn 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://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_off0000f37a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF37A 11012 bytes
SHA-256: c636b8761b0280cd68e0b0fdaaab730acdcfe8a9c5bb1b8d354d766c4943b9bd
font_01_sfnt_off00010d37.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D37 19944 bytes
SHA-256: 2ba0b21bbcdce552115f9feb3ceaf6a38c57b2197ce45a1eeddafb97fec4fa07
font_02_sfnt_off0001402f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1402F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1