Malicious PDF — malware analysis report

Static analysis result for SHA-256 4c6c640c15e8a945…

MALICIOUS

PDF

73.1 KB Created: 2021-09-25 12:55:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 021260d6fd7b7b76a07a9086487d6109 SHA-1: 89e5ed6a18e43e6421c7dd1cb2339d282b4ccd2d SHA-256: 4c6c640c15e8a9450d8cbedef8a1f588f741a6c28ae4184ef05e78b4dc53172d
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs pointing to various domains, indicating a link farm or redirection mechanism. The ClamAV detection and ML classifier strongly suggest malicious intent, specifically identified as a phishing trojan. While no scripts were explicitly extracted, the PDF structure and embedded URIs are consistent with techniques used to redirect users to malicious sites, potentially for credential harvesting or further payload delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://nomylo.ru/uplcv?utm_term=ffmpeg+android+player PDF link annotation
    • http://arabic.cz/ckfinder/userfiles/files/3320689457.pdfIn PDF document text
    • http://ichieh.tw/uploads/files/202109210414263569.pdfIn PDF document text
    • http://worldofpacifiers.com/editor_uploads/system/files/13314450035.pdfIn PDF document text
    • http://bocghebinhduong.com/media/ftp/file/6014169552.pdfIn PDF document text
    • https://bahamianbrewery.com/ckfinder/userfiles/files/86996293635.pdfIn PDF document text
    • http://kd-council.com/upfile/files/zureledezafi.pdfIn PDF document text
    • http://jfe.hk/userfiles/96068522568.pdfIn PDF document text
    • https://jamiatulbanat.in/wp-content/plugins/formcraft/file-upload/server/content/files/1614d928c72248---zapikedawomajovipizifuwul.pdfIn PDF document text
    • http://ume.civilkozpont.hu/uploads/file/89316635036.pdfIn PDF document text
    • http://flirtproducties.nl/ckfinder/userfiles/files/12105536695.pdfIn PDF document text
    • http://zamdq.com/filespath/files/20210903115819.pdfIn PDF document text
    • http://atenngo.com/admin/sites/site/documents/totateroneboxodivuloxobi.pdfIn PDF document text
    • http://jhdljz.com/userfiles/file/1632172873.pdfIn PDF document text
    • https://dm288.com/slicice/file/78863859107.pdfIn PDF document text
    • http://fonnepal.org/userfiles/file/24481759902.pdfIn PDF document text
    • https://jss-moms.si/upload/File/monexudu.pdfIn PDF document text
    • http://nhatrangpalace.net/app/webroot/upload/files/29690987113.pdfIn PDF document text
    • https://nacituran.com/userfiles/file/tamabokabum.pdfIn PDF document text
    • https://ventadeterrenosurbanos.com/userfiles/file/mavogu.pdfIn PDF document text
    • http://hyunsin.net/userfiles/file/65089769531.pdfIn PDF document text
    • http://plenar.hr/wp-content/plugins/formcraft/file-upload/server/content/files/1614d3f5f6772e---numugus.pdfIn PDF document text
    • http://xingyeknitting.com/userfiles/files/14046030878.pdfIn PDF document text
    • https://pointswestliving.com/ckfinder/userfiles/files/89771575456.pdfIn PDF document text
    • https://horizontire.com/userfiles/file/wodekoz.pdfIn PDF document text
    • http://vigen12.com/userfiles/file/nosusipitowaliti.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_off0000b563.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB563 10668 bytes
SHA-256: d5bb2b96c7a353ea9e3608e023d20d04ea6a513c4f18c419d108e2018140a179
font_01_sfnt_off0000cd7d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCD7D 18912 bytes
SHA-256: 676299ea4231a8368386fecd4cd696f15d11c88402d4d4210a2cd18eb4b0ecb5
font_02_sfnt_off0000fee5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFEE5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1