Malicious PDF — malware analysis report

Static analysis result for SHA-256 c0bdff57c340e065…

MALICIOUS

PDF

88.3 KB Created: 2021-06-29 10:29:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 7e43759c4402ee622f2112891392fa57 SHA-1: ea3649e2dc357b19c8f18e6f8d06efa54aaaa28f SHA-256: c0bdff57c340e0650c10fa2c4048a4c6a13685951fc315ad1410a2c75f2be7c8
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file contains embedded JavaScript and a large number of external URIs, many of which point to compromised CMS upload directories. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates the document is a non-clustered link farm on disposable hosting, suggesting an attempt to redirect users to malicious sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9970

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://wastran.ru/uplcv?utm_term=amy+lee+son
    • http://stroynerud-sm.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160b55eae41eb1---52414036917.pdf
    • http://alpha-th.com/userfiles/file/tuwonadeg.pdf
    • https://www.gml.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b935d51059f---mewibudab.pdf
    • http://jeugdopdewetenschapsagenda.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1609c35777598b---suserupetogaxa.pdf
    • http://www.trafikyaren.com/wp-content/plugins/super-forms/uploads/php/files/sl3e3s37aumnepni7h93g2tqa2/22217782927.pdf
    • http://hungthanhauto.com/luutru/files/45030483377.pdf
    • https://webmodels.studio/wp-content/plugins/formcraft/file-upload/server/content/files/1608127d39c87d---geverowijakixepesexanavon.pdf
    • https://die-elke.de/cms/elke_page_files/file/46334235663.pdf
    • http://iwishop.hu/file/vipuzekotinute.pdf
    • https://harom.ro/files/file/15139348909.pdf
    • http://www.marcelasemper.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609abd3e991ec---wezulolurodupowotavi.pdf
    • http://nawaress.com/webroot/js/ckfinder/userfiles/files/kewuwewuvorufobolede.pdf
    • http://www.moteco.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160adab4744dd8---fupulejisumizapopudowigup.pdf
    • https://www.sevgiliyevideo.net/wp-content/plugins/formcraft/file-upload/server/content/files/160859abd80ccf---monel.pdf
    • https://angkortaxiservice.com/userfiles/file/21110063917.pdf
    • https://vigiweb.cl/dinamicos/files/file/zagemewenubikivol.pdf
    • http://chukgoobok.com/files/fckeditor/file/rubobituwuloguvabuxeduvi.pdf
    • http://allseasonsart.com/uploads/fck_uploads/file/51480889074.pdf
    • http://autoset66.ru/admin/ckfinder/userfiles/files/gerifuwovasomipelob.pdf
    • http://hillcountryawningsandsunscreens.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e21e534835---35585189591.pdf
    • https://shiokuda2.com/contents//files/malujivizasif.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_off0000fa5b.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFA5B 16792 bytes
font_01_sfnt_off0001126d.bin
df2fbcb146dbb2930c5892a1e8878ffb6b935713af800b30d4c2e61a3ae0b334
pdf-font-stream PDF embedded font (sfnt) at offset 0x1126D 16680 bytes
font_02_sfnt_off00013d54.bin
326deb735210d9410a86f49fbb03a4b94ad4112f6a56594370a667adb5f54b47
pdf-font-stream PDF embedded font (sfnt) at offset 0x13D54 9912 bytes