Malicious PDF — malware analysis report

Static analysis result for SHA-256 51f74a9a15c0dd9f…

MALICIOUS

PDF

84.2 KB Created: 2021-07-23 20:30:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 42c9a80b7bc7dda8d52f078084ce3fcd SHA-1: 25f232365bb6dd2a5e6caa9dbe52ca3c9031938a SHA-256: 51f74a9a15c0dd9fbf458dcbaa649ca0b4b44d084619b747e7ef46efe7a3a5cb
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, a common technique for executing malicious code within documents. Heuristics indicate the PDF acts as a link farm, directing users to compromised WordPress uploads and other disposable hosting sites, likely for phishing or malware distribution. The ML classifier and ClamAV detection strongly support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9924

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 http://yesilderecine.com/admin/editor_resim/file/56056115312.pdf
    • http://purepoem.com/resource/docContentImg/file/2021-07-22/a9ffaa1177f2ead8084c34c5d7c591b9.pdf
    • https://codecs.roimages/file/50074808689.pdf
    • http://www.radioemka.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b6805628ee6---80412663914.pdf
    • https://roweryelectra.eu/app/webroot/uploads/file/16240009309378.pdf
    • https://mimpishio1bet.net/contents//files/mirodamoxezij.pdf
    • http://midel.me/userfiles/file/vurijubepilumifak.pdf
    • http://zhouzhuank.com/v15/Upload/file/2021716651207680.pdf
    • http://gostium.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608a1e057b876---68957451105.pdf
    • https://cwlighting.com/wp-content/plugins/super-forms/uploads/php/files/766d31ef7f33ce260acc7da69e5aa86d/buwexolobo.pdf
    • https://accu-split.com/userfiles/files/83991682629.pdf
    • https://systematix.pl/userfiles/file/sugutewukuzufodaboj.pdf
    • http://acecaalcoy.com/userfiles/file/wofivogubotojajexaxir.pdf
    • http://aarogyamedico.com/userfiles/file/17842103493.pdf
    • http://reiki-roots.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160ab9fa66281d---46019618074.pdf
    • https://yidinfo.net/wp-content/plugins/super-forms/uploads/php/files/i60g0n6cbr38kq02bnug0nt6ge/26652392712.pdf
    • http://packturf.fr/files/58576855416.pdf
    • http://manufim.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/1607a4c87540e2---29515828948.pdf
    • https://mmagame.com/userfiles/file/62284954193.pdf
    • https://www.helpagesl.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a4d21140de5---gekufedubefokesul.pdf
    • http://gunjanjain.com/app/webroot/js/uploads/files/25245516586.pdf
    • http://kino-cosmik.ru/sadm_files/58838776982.pdf
    • http://mgmkt.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160c1f9aa7debf---2685807655.pdf
    • https://atraba-holding.com/userfiles/file/73480371693.pdf
    • https://estidevelopers.com/wp-content/plugins/super-forms/uploads/php/files/af04c098ac9ba9b2a1e9d0b4f43a3d00/65236120661.pdf
    • https://cafesca.org/ckfinder/userfiles/files/xogug.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=tamil+old+songs+1980+mp3+online+play
    • 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_off0000e420.bin
0c32fd14c7d0b9ea22fbb894c5252e46e35ea5ba047da554e8d3e19efd4aad11
pdf-font-stream PDF embedded font (sfnt) at offset 0xE420 16584 bytes
font_01_sfnt_off00010f41.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10F41 16792 bytes
font_02_sfnt_off00012758.bin
4cf409d05bd1a772b1f2377bc9fa8c9f06b74e919b944fd6f55f0a878e0a63e8
pdf-font-stream PDF embedded font (sfnt) at offset 0x12758 11336 bytes