Malicious PDF — malware analysis report

Static analysis result for SHA-256 34b727b7cd4a6f99…

MALICIOUS

PDF

87.0 KB Created: 2021-06-30 07:22:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 340c5ec3809cebed5bb0050717b48138 SHA-1: 71f7238a5878f5f9ebdcb314566a504b7c8105d3 SHA-256: 34b727b7cd4a6f99d5c0355a74624f439a40042937e285603012fd1caa49c3e8
164 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 upload directories, suggesting a link farm designed to distribute malicious content. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or malware distribution. The document body is heavily obfuscated and unreadable, providing no direct textual clues to its purpose beyond what is inferred from the heuristics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

Heuristics 7

  • 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.
  • Fake invoice / payment lure low SE_INVOICE_LURE
    Document contains invoice or payment language paired with an action verb — useful context when combined with link, macro, or attachment indicators
  • 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://rmissio.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1607edb14684b1---tavaxefifa.pdf
    • https://wkd-uk.com/wp-content/plugins/super-forms/uploads/php/files/7dbcb6427b30d3f8fa41cb1035b5b3bb/59421676912.pdf
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/8728dc00313de33f1c50695f60729170/motufeg.pdf
    • http://imi.vc/upload/files/dojabusamupabubogudiperak.pdf
    • https://rebates.forex/wp-content/plugins/super-forms/uploads/php/files/4dhq92qhghll9aqhkm8bejn2r5/kefoduwe.pdf
    • http://innotack.com/userfiles/files/bosamatirusikopekidi.pdf
    • https://www.jemelectric.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a72706a3203---lalugedusozimebefatofefe.pdf
    • http://botanicgardenscafe.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160a954b0d6129---jetadijexotewadosegeza.pdf
    • http://jjinline.org/file_upload/file/43609890118.pdf
    • https://sckprime.com/wp-content/plugins/super-forms/uploads/php/files/83edc350a923b1d587dc900789ef8ecd/54212597655.pdf
    • http://www.infranetltd.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076e3bb39d1e---tunixobopelijojarewunone.pdf
    • http://argra.rs/wp-content/plugins/formcraft/file-upload/server/content/files/160bc6bbe2515c---dexadiwegotajusi.pdf
    • https://www.heainc.com/wp-content/plugins/formcraft/file-upload/server/content/files/160752e3e89604---judevaranamepilu.pdf
    • http://allamericannursing.com/userfiles/file/81288276057.pdf
    • http://www.cargeacrew.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160750dd8120cc---14893362068.pdf
    • https://www.skyline-recruiting.com/wp-content/plugins/super-forms/uploads/php/files/3b5a90d9b2c4d5ef174593be628d7af5/tukakotepomidezax.pdf
    • https://www.areatransfers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b9635164ce1---81312349011.pdf
    • https://www.18fire.com/wp-content/plugins/super-forms/uploads/php/files/0870598cc4a8dc26b0c83f7de8a4ae18/44313145970.pdf
    • http://penzionriverside.cz/files/file/5522411460.pdf
    • http://conservationenergy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a5c5fe09f78---87056342842.pdf
    • https://alfa-pechati.ru/wp-content/plugins/super-forms/uploads/php/files/d55b743712444f0aa654bc0ee026a79d/23882541899.pdf
    • https://ag-concept.ru/wp-content/plugins/super-forms/uploads/php/files/c38567751973ac45f94ce3409e61b4b3/14599943416.pdf
    • https://go2germany.ru/files/file/zowivoteberi.pdf
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a984a93ecff---43434086045.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=accounting+standards+ifrs+and+gaap
    • https://bxthirteen.wpengine.com/wp-content/plugins/super-forms/uploads/php/files/62cacd41faff1ed77261beeda2d6684d/84179627171.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f272.bin
9432969ceb912b656cf8709be14fc9f783a9a142965681bfd317813d6477e0fc
pdf-font-stream PDF embedded font (sfnt) at offset 0xF272 16756 bytes
font_01_sfnt_off00011e09.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11E09 16792 bytes
font_02_sfnt_off00013620.bin
2127731b9339017cdf3eeb28a2286ffbef0279db7b5059e558de625d128dbdf8
pdf-font-stream PDF embedded font (sfnt) at offset 0x13620 10700 bytes