Malicious PDF — malware analysis report

Static analysis result for SHA-256 cff90eb371efb7d9…

MALICIOUS

PDF

89.1 KB Created: 2021-07-03 12:01:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 3e9ebc7d175a0b4e0d5c6bf3bb49ce27 SHA-1: 286e857193d2d5740b23e81d9775461dd735b94b SHA-256: cff90eb371efb7d97327f0eaf9e3d177ee3ef6c2f9cfa13c5d0d7adf855d5ff2
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to compromised WordPress sites, indicating a link farm designed to host or redirect to malicious content. ClamAV detection and ML classification strongly suggest this PDF is malicious, likely a phishing or trojan delivery mechanism. No scripts were extracted, but the structure and URL patterns are consistent with malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9961

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://www.webhisto.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16099bfd9e65d0---wedutizujal.pdf
    • https://www.varishastalari.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ea2b3afe71---94382778941.pdf
    • https://whiteelephant.co.in/wp-content/plugins/super-forms/uploads/php/files/63387f1612b86c59ed6af4e44fa99e02/merix.pdf
    • https://tkpmission.org/wp-content/plugins/formcraft/file-upload/server/content/files/1608ac1cf534af---xadomumuguronujeboze.pdf
    • https://transport-vehicules.fr/userfiles/file/reganefonegas.pdf
    • https://doitsolutions.co/wp-content/plugins/super-forms/uploads/php/files/e4aaf21f445cc7301528f09e36812457/83603701936.pdf
    • http://www.bestlifepolicy.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160803ef0048d9---4972828780.pdf
    • https://nscs.org/wp-content/plugins/super-forms/uploads/php/files/f0e0acc2ddf7302b83dc90ddb0591410/11227117569.pdf
    • http://bean2beenefamilytree.com/clients/60578/File/35889260990.pdf
    • https://rosemonttherapy.health/wp-content/plugins/super-forms/uploads/php/files/uor3slukg0tbb4p3sitbm0lpic/17561209047.pdf
    • https://accesoriosalmayor.com/images/userfiles/file/22434016515.pdf
    • http://evopizza.lt/ckfinder/userfiles/files/81391288550.pdf
    • http://guojingmall.com/userfiles/file///pazigivarugekuxerut.pdf
    • https://g-ortho.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a13f220f4b4---18695221247.pdf
    • http://cnpair.com/userfiles/file/28647756447.pdf
    • http://altinay-law.com/images/file/rifupokaxunu.pdf
    • http://www.ellisrasbetonwerke.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160aad5f52881d---xerukabogamofegoluzisuxor.pdf
    • https://sellos-mecanicos.com/wp-content/plugins/super-forms/uploads/php/files/34d7b43bb3d505a8a40407f6adc738dc/27171880818.pdf
    • https://www.nobleorthodontic.com/wp-content/plugins/super-forms/uploads/php/files/c37cfbe046f1a8d9d927f678d9fcf795/zokadele.pdf
    • http://getem.pl/files/file/37739192294.pdf
    • http://www.patricktennis.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1608c8d64f1879---71078575275.pdf
    • http://moveisgarciadigital.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160d807ac97de4---94604305836.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=classic+pirate+songs
    • 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_off0000fa26.bin
59a219afc264a011954344c3deb7f86f95446254704aee80dbcb039726327216
pdf-font-stream PDF embedded font (sfnt) at offset 0xFA26 10580 bytes
font_01_sfnt_off0001126c.bin
2831a76ac201181c62835a3c294b974cb10728219a6ff2dac64dce147e6c7222
pdf-font-stream PDF embedded font (sfnt) at offset 0x1126C 17212 bytes
font_02_sfnt_off00013f74.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13F74 16792 bytes