Malicious PDF — malware analysis report

Static analysis result for SHA-256 a6b8d6eab4c2e839…

MALICIOUS

PDF

88.4 KB Created: 2021-06-29 01:38:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 6bab894d28286d2dfbb0df6d994a5d82 SHA-1: c8cc088993bad860d83b63d84fd3868481ca00e1 SHA-256: a6b8d6eab4c2e839eb763c14cce87d9c145fcd0f3ab2d9d5c4aa994f02f8d875
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains an embedded JavaScript stream and numerous external URIs, many of which point to compromised WordPress sites acting as link farms. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or malware delivery through these linked sites. The embedded JavaScript is likely used to facilitate the redirection or obfuscate the malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://www.hamburgeriaagricola.com/wp-content/plugins/super-forms/uploads/php/files/1rqgcbmacfstrr4kgkhceuacto/repubazewizaw.pdf
    • https://tusenfotingen.nu/anvandarbilder/108/files/57931516821.pdf
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b67a67f5cf.pdf
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/3f848c97611b90e430654d698b338a72/sopinaxupul.pdf
    • http://thebeautyofdesign.nl/ckfinder/userfiles/files/xasuvepodigoba.pdf
    • https://unitedcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084cd8491245---76879959634.pdf
    • https://eyestech.in/wp-content/plugins/super-forms/uploads/php/files/n1mo6md71mqpq7kfbio155825l/19688534568.pdf
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608246ca151cf---33448010191.pdf
    • http://www.peplex.it/wp-content/plugins/formcraft/file-upload/server/content/files/160afb3a316f53---95477745400.pdf
    • https://www.ideaklinik.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1607f0afe6d529---50901846986.pdf
    • https://pavaniautismschools.com/wp-content/plugins/super-forms/uploads/php/files/5vg5if8qaro41t1qbehie686iu/86966730647.pdf
    • https://wholisticvibrations.com/wp-content/plugins/super-forms/uploads/php/files/268bf2e174c4331ebef464e506228a4a/piwefov.pdf
    • http://www.gainerwindows.ca/wp-content/plugins/super-forms/uploads/php/files/o9lchaucs4m9lkqm1pfrqr4nd7/89457069776.pdf
    • http://hiace-yoshikawa.com/js/upload/files/rumomaxanepajigad.pdf
    • https://forcechicago.com/wp-content/plugins/super-forms/uploads/php/files/08d75848e2b5791d94f1cb796552c07b/pizuletezoju.pdf
    • https://riverasphotovideo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d1b64a2fcc0---fonuwixibojuw.pdf
    • https://www.jahnigterbraak.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16073017d9f83d---bebavo.pdf
    • https://bettenbaehren.de/wp-content/plugins/formcraft/file-upload/server/content/files/160abacfba7aab---fuvedixukubitefimenijud.pdf
    • https://renebeumer.nl/userfiles/file/37554841792.pdf
    • https://prolocolidodisavio.org/ckfinder/userfiles/files/fexelolawepoxa.pdf
    • http://ambulanceservice.pl/userfiles/file/kojinosafu.pdf
    • http://www.northeastmarquees.com/wp-content/plugins/super-forms/uploads/php/files/fd6a4b9a9b83f553aab0da49d3102657/53926501676.pdf
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/e5e58186ee2c1bdf1e3bac04eab0e75d/76359364735.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=gdp+and+well+being
    • 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_off0000f99b.bin
1e99e1335413e6825c6987366e07917c5720d29ecc68f8201a737dee5117a97c
pdf-font-stream PDF embedded font (sfnt) at offset 0xF99B 10344 bytes
font_01_sfnt_off000110a5.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x110A5 16792 bytes
font_02_sfnt_off000128b7.bin
2e1a29a5d194a95c1ea6cde56c4e5e571af51a741ad604ed8d67ff64f234e695
pdf-font-stream PDF embedded font (sfnt) at offset 0x128B7 16956 bytes