Malicious PDF — malware analysis report

Static analysis result for SHA-256 d92df4ef3e797b36…

MALICIOUS

PDF

74.7 KB Created: 2021-09-13 21:28:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: c5a46e39e88d6d6bdf43131f8a5ede33 SHA-1: 2f1825c59a47e5581f15719c891e32e006bfa7c0 SHA-256: d92df4ef3e797b368823b53df4caeb2a675fb76fcbf453a8164e77912515e18b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous embedded URLs, many of which point to disposable hosting or compromised CMS upload directories, indicative of a link farm designed to obscure malicious destinations. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution, aligning with the Spearphishing Attachment technique. While no scripts were extracted, the structure and URL patterns are common in campaigns distributing second-stage payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

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 http://exosushi.com/uploads/files/33696803438.pdf In PDF document text
    • http://bubb.cn/up_file/file/jipakofalodi.pdfIn PDF document text
    • http://schokobrunnen.com/idata/49435348786.pdfIn PDF document text
    • http://cathugo-yachts.de/res/wysiwyg/file/9813729479.pdfIn PDF document text
    • https://aquatrustfina.com/userfiles/file/42432373672.pdfIn PDF document text
    • http://njchemland.com/upload/files/23240846457.pdfIn PDF document text
    • http://bulmarconsult.com/files/74443907417.pdfIn PDF document text
    • https://o-dance.com/upload/files/bafugebige.pdfIn PDF document text
    • http://leap-egypt.com/wp-content/plugins/formcraft/file-upload/server/content/files/161315aa758e91---wemuzinomonivikopil.pdfIn PDF document text
    • http://zh-huaxun.com/uploadfiles/files/19371078452.pdfIn PDF document text
    • https://hightechrustremovers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613194ebdbda6---jipogigawamebidel.pdfIn PDF document text
    • https://asiantms.com/ckfinder/userfiles/files/1916685311.pdfIn PDF document text
    • https://5ky13lu3-1251.com/contents/files/woxogas.pdfIn PDF document text
    • http://www.olympussverige.se/wp-content/plugins/super-forms/uploads/php/files/hu1i2kefrtdujuos4brevl94dk/8027719646.pdfIn PDF document text
    • https://autoandtruckrepair.net/nbloom/fckuploads/file/vupewuwe.pdfIn PDF document text
    • http://ylpqzl.com/ckfinder/userfiles/files/27630413978.pdfIn PDF document text
    • https://maydangson.com/vietkiendo/upload/file/bowotelixudine.pdfIn PDF document text
    • http://www.heksan.com.pl/file/57174385642.pdfIn PDF document text
    • https://anandamsanyal.com/userfiles/file/vuwitujutap.pdfIn PDF document text
    • http://ecohort.com/userfiles/files/38600301704.pdfIn PDF document text
    • http://wawabed.pl/uploads/userfiles/file/54374398354.pdfIn PDF document text
    • https://www.gurgy.net/ckfinder/userfiles/files/25677088055.pdfIn PDF document text
    • https://davidfoleyinc.com/userfiles/file/58130007828.pdfIn PDF document text
    • http://srs-budapest.hu/uploads/files/55438959999.pdfIn PDF document text
    • http://geostudio.eu/userfiles/files/43862902842.pdfIn PDF document text
    • https://ctcitsupport.com/media/files/4392138284.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=tubemate+pc+software+downloadPDF link annotation
    • 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_off0000be34.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBE34 17684 bytes
SHA-256: 158adb86346bd6acb70122ed6741c6129e70c42ea6ed1c534093b1cdcfa0dab9
font_01_sfnt_off0000ebba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBBA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000103d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103D1 10976 bytes
SHA-256: 121abb46ad70608490f71d1a7d6cbe04adf499312032fc621bbc600191a99175