Malicious PDF — malware analysis report

Static analysis result for SHA-256 c517bf3b212ace18…

MALICIOUS

PDF

80.2 KB Created: 2021-09-09 12:15:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: ad571d961917fa64e6ef1a71199dc8ad SHA-1: b5b1fccfe96ccd167224a45006737ef56afe707a SHA-256: c517bf3b212ace187b33c9a654d7439320b4b76c81143af8b377459b1d331690
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 contains numerous embedded URLs that form a link farm, with several pointing to compromised WordPress sites or disposable hosting, suggesting a phishing or malware distribution scheme. The PDF structure and embedded URLs are consistent with techniques used to lure users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://laborke.ru/uplcv?utm_term=honkai+impact+3+team+build PDF link annotation
    • http://www.naturhalles.fr/fckeditor/userfiles/file/suvojedinesijidug.pdfIn PDF document text
    • https://pmms-online.com/assets/file/zisabejomoxi.pdfIn PDF document text
    • https://tidurmalam2.com/contents/files/41709126453.pdfIn PDF document text
    • http://kindervakantieweekdeurne.nl/wp-content/plugins/formcraft/file-upload/server/content/files/161314f88c372f---6580766955.pdfIn PDF document text
    • https://ip-pharma.net/data/files/walesu.pdfIn PDF document text
    • https://imagebeaute.fr/userfiles/file/zetuzidi.pdfIn PDF document text
    • http://airsoft1.ro/files/file/bivatunobugatizukokojuf.pdfIn PDF document text
    • http://transportdiverse.com/uploads/files/51128159204.pdfIn PDF document text
    • http://vtracauto.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613759672ae24---fojawevubibal.pdfIn PDF document text
    • https://tattica.byespresso.com/app/webroot/files/upload/files/nitapa.pdfIn PDF document text
    • http://styrexon.cz/userfiles/file/27487273879.pdfIn PDF document text
    • http://skipjackpoke.com/ckfinder/userfiles/files/69874768613.pdfIn PDF document text
    • http://tcsm62.org/uploads/news/file/34402827616.pdfIn PDF document text
    • https://www.sabiamente.es/wp-content/plugins/formcraft/file-upload/server/content/files/1613079f6a6a13---kefotuwapekuzub.pdfIn PDF document text
    • https://auf.vn/wp-content/plugins/super-forms/uploads/php/files/noov4qb7poph1ob9oue6bfi4b0/bawewif.pdfIn PDF document text
    • http://medicaldistri.com/ckfinder_files/files/55232550114.pdfIn PDF document text
    • https://fminterativa.net/cms/plugins/ckfinder/userfiles/files/52521987278.pdfIn PDF document text
    • http://cnmrobotics.com/files/files/8441663031.pdfIn PDF document text
    • http://gildiamasterov.ru/userfiles/file/74724351315.pdfIn PDF document text
    • http://childconnect.com/swi/fckfiles/file/62688937278.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_off0000d65a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD65A 10904 bytes
SHA-256: 5a3a5405fb904cf80da77c068c969e00fd89128bb50f2385f64a41545cd694a3
font_01_sfnt_off0000ef4d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF4D 17104 bytes
SHA-256: 320450e98f7ee2e36d0597fd9fe4c773bc338eac3d1330b6c04d35e8481ff11f
font_02_sfnt_off00011b61.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B61 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1