Malicious PDF — malware analysis report

Static analysis result for SHA-256 c5d3679aafb56308…

MALICIOUS

PDF

71.3 KB Created: 2021-09-26 22:38:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: b7e5a68c324582902865d842417921a2 SHA-1: c56c3cede22c8933e86a0f48b741aeab2af7d204 SHA-256: c5d3679aafb56308a499954d6edcb0126763ce03a64f973425b8db203d758d2d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a large number of links, many pointing to compromised CMS upload directories, indicating a link farm designed to lead users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution through these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9986

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://www.lucaslobker.com/minor/ckfinder/userfiles/files/funatajovefexaxemanivowiv.pdf In PDF document text
    • http://jikaramen.com/uploads/files/mepenudavuneji.pdfIn PDF document text
    • http://www.greenfield-sustainability.com/images/files/kanav.pdfIn PDF document text
    • https://www.caissedesecolesdu5eme.fr/backoffice/ckfinder/userfiles/files/45901938032.pdfIn PDF document text
    • https://www.hadlowsecurityshutters.com/wp-content/plugins/super-forms/uploads/php/files/83b4022259c30ab37ba9599959aca4f6/jowajodixi.pdfIn PDF document text
    • https://www.uniqueartzz.com/wp-content/plugins/super-forms/uploads/php/files/8h9audcftmtre2vgl2j509ec6h/jenixikakeg.pdfIn PDF document text
    • https://dongytueduc.com/wp-content/plugins/super-forms/uploads/php/files/htgg8q8o75c368r8mktshpq048/xexafovezumeru.pdfIn PDF document text
    • http://artospace.com/pics/file/95557237600.pdfIn PDF document text
    • https://grouptm2.com/contents/files/88403569313.pdfIn PDF document text
    • https://wanna-drive.nl/files/File/xulatedalekuwebiba.pdfIn PDF document text
    • http://rvhifi.cz/files/file/26064470722.pdfIn PDF document text
    • http://igs.compcierge-asia.com/ckfinder/userfiles/files/65358490056.pdfIn PDF document text
    • http://hz-karavany.cz/ckfinder/userfiles/files/2556003089.pdfIn PDF document text
    • http://sonhanint.com/uploadpic/sun/files/202109230015518856.pdfIn PDF document text
    • https://nadrozmerne-sklo.cz/uploads/32014661357.pdfIn PDF document text
    • https://kayakbranson.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131d095b61d6---46957644231.pdfIn PDF document text
    • http://stjconsulting.it/userfiles/files/pulivenutupulajapo.pdfIn PDF document text
    • http://hindel-relax.ch/ckfinder/userfiles/files/xowulodimaverupenenudefak.pdfIn PDF document text
    • http://belgium-ex.com/images/blog/file/82297394965.pdfIn PDF document text
    • https://robertmatzuzi-massagetherapist.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1614f2eed26413---18231476637.pdfIn PDF document text
    • http://timnhanhonline.vn/upload/files/gufonax.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=which+is+faster+brave+or+chromePDF 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_off0000b41b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB41B 10652 bytes
SHA-256: 8f3efa957677dafbb85d8f75c56370b591d3a8a826bc27681c0cb08fdae6db38
font_01_sfnt_off0000cc9d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC9D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e4af.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4AF 16836 bytes
SHA-256: d4aff7203902d682ced6cff4cd69da209eefd137b7453a079c0ef34c9e6937bd