Malicious PDF — malware analysis report

Static analysis result for SHA-256 4c372eb3d71810c6…

MALICIOUS

PDF

78.8 KB Created: 2021-04-28 20:08:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 681fd6888705157ef24d8fef20e04185 SHA-1: 9443fcace9c32d434ed409280ac871acc752c6e9 SHA-256: 4c372eb3d71810c691e1263a174c99db519be08fa49950583e7b02a3f8723e6d
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript T1204.002 Malicious Link

The PDF document contains numerous links to external resources, many of which are hosted on compromised WordPress sites and appear to be part of a link farm. The heuristic 'SE_PASSWORD_ARCHIVE_LURE' indicates the document likely instructs the user to download a password-protected archive, a common tactic to bypass gateway security. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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
  • Password-protected archive handoff high SE_PASSWORD_ARCHIVE_LURE
    Document gives password instructions for an archive or attachment — often used to keep payloads encrypted until after gateway scanning
  • 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.enviedecrire.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d339d3da38---66117626392.pdf
    • https://www.verpoort-bouw.be/wp-content/plugins/formcraft/file-upload/server/content/files/1607636561b9ae---pavatepabixaxelukunifar.pdf
    • https://lisacutler.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084cc1af1609---61800733872.pdf
    • https://www.digitalsofts.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080e192a436a---faletanasixidevozuxoba.pdf
    • https://laneopx.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607edb2d5539c---97528870584.pdf
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607933cc6f2f8---fisefujef.pdf
    • https://theshairpodcast.com/wp-content/plugins/super-forms/uploads/php/files/648aeb4d8056edc4e6d1295780c11cd8/83427730412.pdf
    • https://www.c2commercial.com/wp-content/plugins/super-forms/uploads/php/files/91cf718b7461b03ea1edf829c894f8c5/42199746933.pdf
    • http://www.driftime.ee/wp-content/plugins/formcraft/file-upload/server/content/files/16082ffa0de412---finifenuwarisu.pdf
    • https://snabavto.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072caf1095d6---bekasusozobogezosuwuzaro.pdf
    • http://drvision.org/wp-content/plugins/formcraft/file-upload/server/content/files/16073795c6358f---68082485514.pdf
    • http://sazjah.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082c1b1db11d---72749741185.pdf
    • https://sarujiovalente.com/wp-content/plugins/super-forms/uploads/php/files/4757bmtg36o7q3pmqeu5d9ogv5/9158452327.pdf
    • http://global-gypsum.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d0dc86adeb---24219563193.pdf
    • http://getawaynewzealand.co.nz/wp-content/plugins/formcraft/file-upload/server/content/files/16088b6b59f3c8---liwedesosadupiwowuz.pdf
    • https://formapolis.it/wp-content/plugins/super-forms/uploads/php/files/163135b53166d1f15e5d69609b5fcb05/15307438890.pdf
    • https://choiceenergynetwork.com/wp-content/plugins/super-forms/uploads/php/files/ff37c6c734c50f1652706ba1cb4b98bc/67814099676.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=zip+unzip+freeware
    • 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://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f980.bin
fce2354472a19c51f14e17de5ee34aa495c6dfe243159cd557fba7f71833d50d
pdf-font-stream PDF embedded font (sfnt) at offset 0xF980 4784 bytes
font_01_sfnt_off000109f2.bin
a542de35cc76f643b2c422608eef4dfd2f82f7350c272b0b27881c7310222896
pdf-font-stream PDF embedded font (sfnt) at offset 0x109F2 10904 bytes