Malicious PDF — malware analysis report

Static analysis result for SHA-256 0a349c76833fb1db…

MALICIOUS

PDF

75.0 KB Created: 2021-09-13 00:48:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: a79ef24303aeff05fae056f159b0f4e8 SHA-1: 1f31007487f2505d265d1ad2d11c9b3e8664b53d SHA-256: 0a349c76833fb1dbafff1ef35f3f72c089a7862ea1af3d4831d5b3a55cebe949
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file flagged by ClamAV as a phishing trojan. It contains embedded JavaScript and numerous external URIs, many of which point to compromised WordPress upload directories or disposable hosting, suggesting a link farm designed to redirect users. The ML classifier also strongly indicated maliciousness. The embedded JavaScript likely facilitates the redirection or download of malicious payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://synerhu.ru/uplcv?utm_term=mini+militia+avatar+maker
    • https://ropaalmayoreo.com/images/userfiles/file/63832179717.pdf
    • https://studiogreenwich.ru/wp-content/plugins/super-forms/uploads/php/files/f4326bf875144006b262b9fbdc675559/meditoxojipokofapakalado.pdf
    • https://aznamaste.com/ckfinder/userfiles/files/2810469844.pdf
    • http://digitalqwerty.com/ckfinder/userfiles/files/25263047104.pdf
    • https://ubranni.com/uploader/files/gawitorisajana.pdf
    • http://kaizousha.com/js/upload/files/kiruxoda.pdf
    • http://gingerwooddesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137a89bb92a1---51279286756.pdf
    • http://ketnoikienthuc.com/upload/files/50168172184.pdf
    • http://debten.net/UserFiles/File/1534421652.pdf
    • http://www.uvhk.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e6d6d15467---88281296861.pdf
    • http://quesnelbusinessnetwork.ca/userfiles/file/4907239987.pdf
    • http://gndpta.eu/news_objects/files/nebowosifu.pdf
    • http://eduomania.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613cfac499c88---bonanenodi.pdf
    • http://tuecpa.com/file_media/file_image/file/380761751.pdf
    • http://eugensa.lt/app/webroot/uploads/userfiles/files/9577699540.pdf
    • https://cbolean.com/wp-content/plugins/super-forms/uploads/php/files/f4b74bafd28b1162aa58788f5d5fa2f4/kegiralubur.pdf
    • http://aryajob.com/user_upload/file/84210450244.pdf
    • https://claphamjunction.com.au/wp-content/plugins/super-forms/uploads/php/files/005287750f926fee723ee07750802653/rikim.pdf
    • https://www.limratechnologies.net/wp-content/plugins/formcraft/file-upload/server/content/files/1613245f486e04---segezitilozojej.pdf
    • http://www.ettermanenterprises.com/ckfinder/userfiles/files/37735212930.pdf
    • http://vibrosystem.ro/wp-content/plugins/formcraft/file-upload/server/content/files/161320681bd213---63859919138.pdf
    • https://gea99.com/ckfinder/userfiles/files/leluvojabiguxosasun.pdf
    • https://ajambary.com/userfiles/file/97963920568.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_off0000c23a.bin
b69f187385013b98d14650b999a3ee00d49ed414e22b3fc0eec6ea7551bbe6ee
pdf-font-stream PDF embedded font (sfnt) at offset 0xC23A 17532 bytes
font_01_sfnt_off0000efec.bin
57b6d995273898e270beeea5648013d89f3c5e9edc8b2b1b02f51eeb67d2cdc6
pdf-font-stream PDF embedded font (sfnt) at offset 0xEFEC 10132 bytes
font_02_sfnt_off0001067b.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1067B 16792 bytes