Malicious PDF — malware analysis report

Static analysis result for SHA-256 adc8d851390e9f68…

MALICIOUS

PDF

87.1 KB Created: 2021-06-26 02:17:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: bf1f6b21d3e082f490fc2554947d69ad SHA-1: ec660836d33d17fd98b0691769c375803e862632 SHA-256: adc8d851390e9f68d4287d845db36ca786976adb0712dcc4b5691a18a9214bdd
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous links, many pointing to compromised WordPress installations, indicating a link farm designed to redirect users to potentially malicious sites. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. No scripts were extracted, but the extensive use of external links is the primary attack vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://hoovermaids.com/wp-content/plugins/super-forms/uploads/php/files/158da27e6ff249de2fbaab690e82417f/37166414638.pdf In PDF document text
    • http://test.uebersetzungen-nesselberger.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a25aad59aff---26302920156.pdfIn PDF document text
    • http://www.norestim.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160c72478d7b0b---napob.pdfIn PDF document text
    • https://sitebyside.ru/wp-content/plugins/super-forms/uploads/php/files/8da5676cd6e38922658f0b19c8baf998/wimobilapagavamenememon.pdfIn PDF document text
    • http://coalcreekcentenary.com/clients/5/52/52f735e63eff8706e1a2a73a20aef632/File/zazoxegadolukapuvadu.pdfIn PDF document text
    • http://gruppocinofilomarsalese.com/userfiles/files/lataresufinuvetebinen.pdfIn PDF document text
    • https://c4ir.ae/wp-content/plugins/super-forms/uploads/php/files/5ojba9a6givsb351v0f803oit4/25943605746.pdfIn PDF document text
    • http://ophtalmic-overnight.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160abe7111c2b5---36014300584.pdfIn PDF document text
    • https://law.myvzl.com/wp-content/plugins/super-forms/uploads/php/files/j40q6p0h9e8d0ljq7fvn2cn8st/vigesipolefewibunu.pdfIn PDF document text
    • https://mednet.mk/public_html/upload/userfiles/file/33545770292.pdfIn PDF document text
    • http://securitydirect.it/wp-content/plugins/super-forms/uploads/php/files/b91a1de05c591315e6adc5dd58c2dad0/53042209554.pdfIn PDF document text
    • http://bascobrunswick.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160c713b35b5f6---56938748919.pdfIn PDF document text
    • http://tebsc.com/clients/84181/File/81083057413.pdfIn PDF document text
    • http://geology.ie/wp-content/plugins/formcraft/file-upload/server/content/files/16095d3be1f9c1---lazagikuremubewopatonude.pdfIn PDF document text
    • https://www.kunapak.com/wp-content/plugins/super-forms/uploads/php/files/m217aau82agmralkde6qe7id0l/zofifageloxosafifutifexe.pdfIn PDF document text
    • http://timatey.kz/wp-content/plugins/super-forms/uploads/php/files/98q8mpuncp2cndsbshhh0s3122/zurarajuvatirefu.pdfIn PDF document text
    • http://cerezolorente.com/files/cerezolorente/_repo/file/vepekegedo.pdfIn PDF document text
    • https://adm.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/3e0ef71cb9c08bdc7675d1e52e6fceda/rexilofewitajutesufozap.pdfIn PDF document text
    • https://hps-gruppe.com/wp-content/plugins/super-forms/uploads/php/files/89opl6ed9d15k2pqthlithl25k/33059878109.pdfIn PDF document text
    • http://pwr-tech.ru/userfiles/file/bokeluseregepuju.pdfIn PDF document text
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/2c6d6527abe2ae30e4bae186135094ab/bowotepedox.pdfIn PDF document text
    • http://ajtoablakcentrum.com/_user/file/3358869052.pdfIn PDF document text
    • http://conwaychristian.org/wp-content/plugins/formcraft/file-upload/server/content/files/160c54acb6fffb---34088002718.pdfIn PDF document text
    • http://files.ibiza-ferien.de/file/kikobibedabivumulug.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=an+outline+history+of+english+language+book+pdfPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f182.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF182 16804 bytes
SHA-256: 478946ac80f3d96ca0844938a6bb2b184567a9f6a3188b8581500df5048536b5
font_01_sfnt_off00011d10.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D10 11204 bytes
SHA-256: a930e06a99d2b72cc808346492a0176d1f3952c559492ce1364f3674de65cee5
font_02_sfnt_off000136e3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x136E3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1