Malicious PDF — malware analysis report

Static analysis result for SHA-256 b51e623f27c773ab…

MALICIOUS

PDF

85.9 KB Created: 2021-06-27 11:42:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: cadaa2c81fa4a838ab1bb0fdfe345f75 SHA-1: 71ebdf8d88e16f7e23d96aec1da13870a8e51877 SHA-256: b51e623f27c773ab5aa3c679b0f2c6baab3f264a83129cd72223534fc458d5e2
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as Pdf.Phishing.Trojan. The presence of numerous links pointing to compromised WordPress uploads and disposable hosting suggests a link farm designed to redirect users to malicious sites. No scripts were extracted, but the overall structure and heuristic firings indicate a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://sdyh.gr/wp-content/plugins/super-forms/uploads/php/files/v7g3c8gstrci9toqen290h0ir7/tonodufinotup.pdf
    • https://baptistfriends.org/media/gavunixewuv.pdf
    • http://recrute.fr/files/files/54242166855.pdf
    • https://www.reparaciondebomba.com.ar/wp-content/plugins/super-forms/uploads/php/files/fhs4q6277e9dij634omb2b3ki3/bovuwog.pdf
    • http://ylplj.com/ckfinder/userfiles/files/55916028925.pdf
    • http://agnieszkapawlik.com/userfiles/file/21339450836.pdf
    • https://xn--80aaa1anac6cg.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/f26d9f2d2623388a6fba7bac1e53cd16/82803651442.pdf
    • https://vdbergelectro.nl/wp-content/plugins/super-forms/uploads/php/files/dd09cf898e9c7ede69201d5579f29982/bizepitopi.pdf
    • http://jyotiacademicpress.org/uploads/file/mumulafatol.pdf
    • http://www.europesolidaire.eu/userfiles/files/womidugix.pdf
    • https://whiteelephant.co.in/wp-content/plugins/super-forms/uploads/php/files/e691d9756d99407dbe6d4d9f1ddc0191/tuzewamirebavilivadow.pdf
    • http://aaaexpressheating.com/userfiles/file/43474919116.pdf
    • http://insidethedigitaltrend.com/userfiles/file/lojirojozexax.pdf
    • https://www.lowdoc-loans.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160d46fca380a4---xozafuvosakidisajoxi.pdf
    • http://deltastal.ru/userfiles/file/lolelokamosekidapupegov.pdf
    • http://www.contectrade.hu/fckfiles/file/45909560771.pdf
    • https://eduinfinite.com/wp-content/plugins/super-forms/uploads/php/files/7bb9ef6be7516fad92524fc3cbbc4711/zininojulavekabofi.pdf
    • https://ivfnna.gr/wp-content/plugins/super-forms/uploads/php/files/fb7e2d3fe60c41489cd76e0d75041dfc/18678962791.pdf
    • https://www.ideaklinikbakirkoy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b05f708fd0c---xukewiruserazidaxumebixej.pdf
    • http://vimar.ua/userfiles/files/kiwerinifofeberowakexazif.pdf
    • http://thuduchouse.vn/pics/file/jofatujopuvip.pdf
    • https://www.energetisch-therapeut-estie.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1609af50fadec7---nejatitujinovuxavawo.pdf
    • https://celovechurch.org/wp-content/plugins/super-forms/uploads/php/files/6a29c64310cc89c474f93319258e9e52/xugewizasolev.pdf
    • http://www.myhhsi.com/wp-content/plugins/super-forms/uploads/php/files/82d373b153749241a11c56c30f19bdfc/piwixudiroto.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=best+ever+chocolate+chip+cookies
    • 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_off0000ee5e.bin
890d4ff32c626da5503b3c7595eaf7122324c14845629ac25f3b059ca8e29cda
pdf-font-stream PDF embedded font (sfnt) at offset 0xEE5E 10580 bytes
font_01_sfnt_off000106c1.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x106C1 16792 bytes
font_02_sfnt_off00011ed3.bin
102673e9e166e533b8178963e2f0285949c27c5a361712745c361230412718e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11ED3 16644 bytes