Malicious PDF — malware analysis report

Static analysis result for SHA-256 d03bc22b24c9897a…

MALICIOUS

PDF

75.7 KB Created: 2021-09-12 06:42:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: ebb51d819fd48f2046cc8c7fd436e9aa SHA-1: c9023128bf0fb0e0c269bd0c121270c6c344c193 SHA-256: d03bc22b24c9897a8336c07df528c130b1ce0ef8623724fe69a215f312cbff8b
96 Risk Score

Malware Insights

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

The PDF contains a large number of embedded URLs, many of which point to compromised CMS upload storage or disposable hosting, indicating a link farm. The ML classifier strongly flagged this PDF as malicious. While no scripts were extracted, the structure and URL distribution suggest a malicious intent, possibly for SEO spam or to distribute further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 5

  • 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://upakuika.com/img/file/fibitukefonefugodebejom.pdf In PDF document text
    • http://swapnakoodu.com/fck_uploads/file/55414139097.pdfIn PDF document text
    • http://versobrokers.eu/userfiles/files/mubirobivowagume.pdfIn PDF document text
    • http://konditsionery-odincovo.ru/upload_picture/file/4515084654.pdfIn PDF document text
    • https://www.comperat-89.fr/ckfinder/userfiles/files/65141345597.pdfIn PDF document text
    • https://network-italia.com/file/77677422649.pdfIn PDF document text
    • http://greenglobepms.com/uploads/25988445936.pdfIn PDF document text
    • http://studioambienteterritorio.it/userfiles/files/dugabifedurupok.pdfIn PDF document text
    • http://zhuoer.ltd/userfiles/file/zikibe.pdfIn PDF document text
    • http://www.grundys.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16138d058d75e1---pegojigemutes.pdfIn PDF document text
    • https://loan-financial.com/wp-content/plugins/super-forms/uploads/php/files/beded8d51ae248ff6c1a40b3023a03cb/2761503852.pdfIn PDF document text
    • https://foodexgida.com/uploads/files/vajedugavarabojewap.pdfIn PDF document text
    • http://vdgairconditioning.nl/wp-content/plugins/formcraft/file-upload/server/content/files/161384e0990c1e---vazuselozebukubukox.pdfIn PDF document text
    • http://totoumi.jp/upload/file/30810635713.pdfIn PDF document text
    • http://panova-art.com/files/file/fatemosad.pdfIn PDF document text
    • https://suemsas.com/wp-content/plugins/super-forms/uploads/php/files/7cjl59q6bdfaqgn67ag2l64v30/32815926971.pdfIn PDF document text
    • http://hitecds.com/userfiles/file/53898646569.pdfIn PDF document text
    • http://diagnosticaedilizia.com/userfiles/files/lipinafosazelewomi.pdfIn PDF document text
    • http://xn--76-6kca8aqc6c.xn--p1ai/pic/userfile/73693706412.pdfIn PDF document text
    • http://aksaaydinlatma.com/img/editor/image/file/komapet.pdfIn PDF document text
    • http://forti.in/userfiles/file/megutijolesu.pdfIn PDF document text
    • http://irths.com/upload_files/files/89259860664.pdfIn PDF document text
    • http://www.naraihillgolf.com/admin/userfiles/file/novobigemetiriratif.pdfIn PDF document text
    • http://jinruily.com/UploadFile/file/20210902044701096.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=gta+games+free+androidPDF 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_off0000c5ad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC5AD 10688 bytes
SHA-256: 69e7445070be3f911d650a13f71f2f112af710d53ea8891cb7c71f82744fdae6
font_01_sfnt_off0000de08.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE08 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f61a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF61A 16712 bytes
SHA-256: bda84a968ec7480669082f52de489e65ffbb3a7a3b33e6ddf34fe886e68054df