Malicious PDF — malware analysis report

Static analysis result for SHA-256 a5816e587cb3b481…

MALICIOUS

PDF

166.5 KB Created: 2021-07-01 13:43:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: 55a357c842a5c45d7e14f4184f4a4e75 SHA-1: 1677dc0e18c4ca569184d4e35ff78ec962a1414a SHA-256: a5816e587cb3b481e2bfec4e760c5dcbe346b50c4973786e685e03f86043134c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many hosted on compromised WordPress sites, suggesting a phishing or credential harvesting campaign. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to distributing further malware or leading users to malicious sites. No scripts were extracted, but the link farm structure is a common tactic for initial access.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9903

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://drafthe.ru/uplcv?utm_term=secondary+metabolites+examples PDF link annotation
    • https://www.vbclighting.com/wp-content/plugins/super-forms/uploads/php/files/d0e09815ad8f2d8de3300a60f15741f7/95119696188.pdfIn PDF document text
    • https://perleyparish.org/wp-content/plugins/super-forms/uploads/php/files/698b9fede5d9b2c640737ed864dd0b3e/perefafirizovifiwesomi.pdfIn PDF document text
    • http://for-rent-aalst.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608059eece3bc---panemuvibulowejiwixuxobu.pdfIn PDF document text
    • https://handinhand-daycare.com/ckfinder/userfiles/files/3552367757.pdfIn PDF document text
    • http://www.optionassurance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160bfe87a23458---ludijimenejugiken.pdfIn PDF document text
    • http://www.contectrade.hu/fckfiles/file/zepewigevebimemir.pdfIn PDF document text
    • https://kodcomputers.ro/2664/uploads/tanilizuberaxom.pdfIn PDF document text
    • https://www.ptlittleflower.org/wp-content/plugins/super-forms/uploads/php/files/pcf8f2tqfgmk0d4kqbgc9ubecq/xomisuwufiluxanofasedu.pdfIn PDF document text
    • http://baloneacessorios.com/_upload/file///tepusupavopax.pdfIn PDF document text
    • https://247christianity.org/fckeditor/userfiles/file/218570740911622947678.pdfIn PDF document text
    • http://1qjd.com/upload/files/2021-06-24-10-28-07-CgiqTQVy.pdfIn PDF document text
    • http://www.eflox.net/wp-content/plugins/formcraft/file-upload/server/content/files/16070439420e05---24773857353.pdfIn PDF document text
    • http://accessiblevehicleservices.com/userfiles/file/80416133938.pdfIn PDF document text
    • https://www.democratum.com/wp-content/plugins/super-forms/uploads/php/files/87501f148792a82bd39fe883ee0dfd12/29942535941.pdfIn PDF document text
    • https://pluckywize.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ff46ac5316---valis.pdfIn PDF document text
    • http://vegasoft.hr/wp-content/plugins/formcraft/file-upload/server/content/files/16072391250290---lurogaxat.pdfIn PDF document text
    • http://www.champcaregivers.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606fa64c2e5f2---36857747146.pdfIn PDF document text
    • http://sun-green.be/ckfinder/userfiles/files/gikukanijawobejezulifik.pdfIn PDF document text
    • https://hoovermaids.com/wp-content/plugins/super-forms/uploads/php/files/5d965c336904d17efd5f05179fc44aba/palakudalabofovaxepinutej.pdfIn PDF document text
    • http://www.grundys.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160d66b04b0e17---19575222435.pdfIn PDF document text
    • https://mygenius.ru/admin/ckfinder/userfiles/files/52337079179.pdfIn PDF document text
    • https://floorco.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/7df66febcaacd3a5698a7340e06f14fc/51652901753.pdfIn PDF document text
    • http://shmountaineering.co.uk/wp-content/plugins/super-forms/uploads/php/files/7dsefk66nqppmsff2kkpp1oak7/fagamebapavipipuwex.pdfIn PDF document text
    • http://www.allatpatikapecs.hu/images/file/mosujaneluvajab.pdfIn PDF document text
    • http://www.itbaloch.com/wp-content/plugins/formcraft/file-upload/server/content/files/16093cfa3bece4---80589518107.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_off00022a40.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x22A40 17976 bytes
SHA-256: 6a0acbe147903afd38ba99c935d732071c7454792c637a21069f1e5e0888fbaf
font_01_sfnt_off00025a23.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x25A23 11104 bytes
SHA-256: f788dc23fb9724b969527db31f490582bbb6ca40a49eb2a2f8fb6f5d582b52e5
font_02_sfnt_off000273db.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x273DB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1