Malicious PDF — malware analysis report

Static analysis result for SHA-256 cd9a24813541f3ed…

MALICIOUS

PDF

130.8 KB Created: 2021-06-27 18:46:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 0ee4ec6718c6933442830f7c27d6a202 SHA-1: 1c3f00b8f5b6ca0c98f4e3d3f52d94de40fe7d44 SHA-256: cd9a24813541f3ed1ec4469e2449f6b856ec3cda0ff145a16ccfaf50f0cc0031
156 Risk Score

Malware Insights

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

This PDF was flagged by multiple heuristics as a link farm pointing to compromised WordPress sites and other disposable hosting. The ML classifier and ClamAV also identified it as malicious, specifically a phishing trojan. The embedded URLs suggest a phishing or malware distribution campaign, likely initiated via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

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://medvor.ru/uplcv?utm_term=hppc+test+battery
    • http://oguzlarotomatiksanziman.com/depo/sayfaresim/file/82359183214.pdf
    • http://www.alexgis.com/siteuploads/editorimg/file/fudes.pdf
    • http://arcomproltd.com/userfiles/file/fefugoribenesosu.pdf
    • https://primeodontorj.com/wp-content/plugins/super-forms/uploads/php/files/4a6ecfcbdd0d31d03400598388078566/94126488378.pdf
    • https://www.americanapi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609306b1120d2---gizikedazan.pdf
    • http://j-line.ca/fck_upload/file/demewamirid.pdf
    • https://x-software.cz/data/file/nuvip.pdf
    • https://carcable-bg.com/uploads/pictures/files/moxogitegejomupitilazatog.pdf
    • https://agsposure.org/wp-content/plugins/super-forms/uploads/php/files/78fe6385d2e47496fc34657d093640a0/lugidomezu.pdf
    • https://completecollegestrategies.com/wp-content/plugins/super-forms/uploads/php/files/aa441cc2217ac83c974c2893a2f2b336/86659722048.pdf
    • http://clarksville.net/wysiwygfiles/file/47010871769.pdf
    • http://sunarfactory.com/userfiles/files/82401154466.pdf
    • https://ddriu.hu/wp-content/plugins/super-forms/uploads/php/files/cb9699fdd60dcb7f9485a4e5ecd84e7a/lexulowo.pdf
    • https://mosoptagro.ru/wp-content/plugins/super-forms/uploads/php/files/7bcf87bfda37c2330e0585a22b2f43b9/24407294761.pdf
    • https://susta.vn/userfiles/file/salivaxalutujepijeporagot.pdf
    • http://www.siscbolivia.com/admin/uploaded/fck/file/26101781931.pdf
    • http://naturallabs.fr/userfiles/file/sidedelaxediremerun.pdf
    • http://www.marcado.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16098da25f1d53---vimosaxi.pdf
    • https://miamiuniquelimo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c63cd5b772---7803995158.pdf
    • http://uci.ir/userfiles/file/bowikadidasixile.pdf
    • https://www.properties-thassos.com/wp-content/plugins/super-forms/uploads/php/files/jqga3npik9uvg8pqdhgj8sb58o/14601559642.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_off00019bd8.bin
3d096ca203cfaf7193b384097b4dce83da0ed2939b6005b67a8a74d373dc9f8e
pdf-font-stream PDF embedded font (sfnt) at offset 0x19BD8 19068 bytes
font_01_sfnt_off0001ced0.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1CED0 16792 bytes
font_02_sfnt_off0001e6e7.bin
6886a5ba13e69ebe64c41e326567e511fc22182c729a02c627cc1530e738da6b
pdf-font-stream PDF embedded font (sfnt) at offset 0x1E6E7 10252 bytes