Malicious PDF — malware analysis report

Static analysis result for SHA-256 8e5e1f403e07c05f…

MALICIOUS

PDF

73.0 KB Created: 2021-09-06 09:31:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 3b7b77798a5a4a0ec9b30462ea2dc3a8 SHA-1: 8322151519d31f1e7c8f78454e7e6ecc0ef773ba SHA-256: 8e5e1f403e07c05fb244d6bdc60589b588b60c2d657c3e92e1d950eb8f347afa
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous embedded URLs pointing to compromised WordPress uploads and other disposable hosting sites, likely to manipulate search engine results or redirect users to phishing pages. No scripts were extracted, but the PDF structure and embedded links strongly suggest a phishing or SEO poisoning attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9908

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://oniceh.ru/uplcv?utm_term=add+and+subtract+rational+expressions+worksheet+pdf PDF link annotation
    • https://asiquim.com/ckfinder/userfiles/files/boxaposifawozenoganopowe.pdfIn PDF document text
    • https://www.sahabatkeluargahomecare.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609d2f6fa7160---lezawudugikebababujob.pdfIn PDF document text
    • http://podlahyadvere.sk/editor_uploads/system/files/30005903044.pdfIn PDF document text
    • https://weeb.nu/userfiles/file/buduxibomukoduvogubowovub.pdfIn PDF document text
    • http://yangpupark.com/uploadfile/files/14854031954.pdfIn PDF document text
    • http://cen7dias.es/userfiles/files/vekesudozozunido.pdfIn PDF document text
    • https://www.femregenx.co.za/wp-content/plugins/super-forms/uploads/php/files/me0ehdm0lremc86pgi3hiavagf/80610498013.pdfIn PDF document text
    • https://safetypadlocks.eu/eurostyl/photos/file/vonarutabikegariv.pdfIn PDF document text
    • https://adasms.fr/userfiles/file/67362795709.pdfIn PDF document text
    • https://linhquan-group.com/upload/ck/files/36150079519.pdfIn PDF document text
    • https://asiatravel.kg/wp-content/plugins/super-forms/uploads/php/files/ae572de364bd42cedfacb20699fa6fe4/pomolonavagipat.pdfIn PDF document text
    • https://muratay.nl/userfiles/file/demeriponagebaveguwanox.pdfIn PDF document text
    • http://bahattinburyan.com/userfiles/file/73296671914.pdfIn PDF document text
    • http://jinwoosmc.com/userfiles/file/birefogunusirabuxisijefu.pdfIn PDF document text
    • https://femagnet.com/upload/edu/article/file/vonapowadakeguloziravo.pdfIn PDF document text
    • http://radiopoint.cz/userfiles/file/41453074846.pdfIn PDF document text
    • https://maydongy.com/wp-content/plugins/super-forms/uploads/php/files/l5ik0mu3nu6c214kg0t2p9hp0b/78422033173.pdfIn PDF document text
    • https://www.la-melodie-des-saveurs.fr/ckfinder/userfiles/files/xesoxufetedajujupim.pdfIn PDF document text
    • http://dabaizhongxue.com/upload_fck/file/2021-6-30/20210630083414498831.pdfIn PDF document text
    • https://apc-algercentre.dz/ckfinder/userfiles/files/kunixon.pdfIn PDF document text
    • http://xperion.hu/wp-content/plugins/super-forms/uploads/php/files/cf848c4c3e5ab82f8f2e1bbaceb74465/pexeti.pdfIn PDF document text
    • https://cffcommunications.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/16082777266001---foxadobiwixozov.pdfIn PDF document text
    • http://neurooperations.com/ckfinder/userfiles/files/megexoge.pdfIn PDF document text
    • http://kesherisrael.com/uploadEditor/files/30227830704.pdfIn PDF document text
    • http://domeinbeverdonk.be/assets/files/file/95809556127.pdfIn PDF document text
    • http://kraljicabih.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608702140b07a---nirafovuvunezexin.pdfIn PDF document text
    • http://tsradviseurs.nl/mailing/images/photo/file/43573014639.pdfIn PDF document text
    • 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_off0000bc19.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBC19 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d430.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD430 11220 bytes
SHA-256: c2ece3cdfd3157b7c29da2b7e59988e5f6a91651631b14a1af0909385273ea57
font_02_sfnt_off0000ee4c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE4C 15428 bytes
SHA-256: 0cedbaba04c6fea81894c650b83e29c9d8b7f1c4b86914cddc782587c154c474