Malicious PDF — malware analysis report

Static analysis result for SHA-256 b58cb543d9a15720…

MALICIOUS

PDF

86.4 KB Created: 2021-09-15 08:29:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: c0dd50ec6baac8f1a489c6a0503596fa SHA-1: edd1f9335859c3b7581c0a5e9dc496285a3e423e SHA-256: b58cb543d9a157203d025505439e8fcedac851d415689626e4d554b55116873d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is identified as malicious by ML classifiers and ClamAV, with multiple heuristics indicating it's a link farm pointing to compromised CMS uploads and disposable hosting. The embedded URLs suggest a phishing or malware distribution attempt, likely initiated via spearphishing attachment. No scripts were extracted, but the PDF structure and URL patterns are indicative of malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://coretry.ru/uplcv?utm_term=the+48+rules+of+power+pdf PDF link annotation
    • http://okna-stv.ru/userfiles/files/wududivugevuxoxutesufom.pdfIn PDF document text
    • http://bangkokmagnetwire.com/ecodev_test/image_system/files/namuwox.pdfIn PDF document text
    • https://edouardweil.com/userfiles/file/lenixizuvatevofuwizafat.pdfIn PDF document text
    • http://agisinfo.ru/uploads/content/files/51576757583.pdfIn PDF document text
    • http://www.medicalalliedtraining.com/wp-content/plugins/formcraft/file-upload/server/content/files/161319c6831564---93306375447.pdfIn PDF document text
    • http://yacpa.org/yacpafiles/file/vokifujuletawubakutimu.pdfIn PDF document text
    • http://indigobaby.eu/upload/files/7648980593.pdfIn PDF document text
    • http://www.mezmat.ru/ckfinder/userfiles/files/jezobuzagodutabakatamak.pdfIn PDF document text
    • http://spzpoz-zdunskawola.pl/upload/file/44311625288.pdfIn PDF document text
    • https://cnn-logistics.com/asset/files/gugiserejojejuxebive.pdfIn PDF document text
    • https://citrasas.com/ckfinder/userfiles/files/31815079879.pdfIn PDF document text
    • http://consade.com/userfiles/file/14158087199.pdfIn PDF document text
    • https://mahae.hu/files/files/63871216869.pdfIn PDF document text
    • https://www.ayersworthglen.com/wp-content/plugins/formcraft/file-upload/server/content/files/161408f4b02c87---61902597506.pdfIn PDF document text
    • http://art-ball.net/files/file/judusopololobokepomuxex.pdfIn PDF document text
    • http://daoltrading.com/userData/board/file/mozojimuxuteguloxedir.pdfIn PDF document text
    • https://hoovermaids.com/wp-content/plugins/super-forms/uploads/php/files/ea23a39d94b5b7c567ad2b7099f57ada/labes.pdfIn PDF document text
    • https://kantankacreative.com/wp-content/plugins/super-forms/uploads/php/files/0bc6cd397c6f68e773a2497f4859ba7d/rigisik.pdfIn PDF document text
    • http://kingkady.com/uploadfile/files/vitoba.pdfIn PDF document text
    • https://mandarinusa.com/userfiles/file/1631613929.pdfIn PDF document text
    • https://drivingschoolofnorthtexas.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614000427ae41---74226837254.pdfIn PDF document text
    • http://bagliodeimille.it/userfiles/files/pazarogukilotareduwu.pdfIn PDF document text
    • http://admio.ru/wp-content/plugins/formcraft/file-upload/server/content/files/161330c4c4e8b8---safipesakikagukijolak.pdfIn PDF document text
    • http://kingsap.com/file_media/file_image/file/noraduvogikutumogibari.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_off0000eb75.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB75 18492 bytes
SHA-256: 387cfcee5661c2098ce5a472358ca9f9ef85c380b4e92315c7fa795fb161baeb
font_01_sfnt_off00011b20.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B20 10576 bytes
SHA-256: e9f9b77871f1b1616b8fff79ebdec4a7602cb94e50b0dcb4719518bbb1f88edc
font_02_sfnt_off00013387.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13387 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1