Malicious PDF — malware analysis report

Static analysis result for SHA-256 f7c979aebf84f7ce…

MALICIOUS

PDF

76.4 KB Created: 2021-09-06 03:24:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 73d1feca79928955cbbc3d8e56fc3213 SHA-1: ab3ca3ffabe0cbbe459e5aeb9f3abc2d21815193 SHA-256: f7c979aebf84f7ceeecbfffa3eda941d5718f2d5d9e6376a5b49dd27ca0be8f5
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous embedded URLs, many of which point to compromised WordPress sites. The 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' heuristics indicate a deliberate attempt to create a link farm for malicious purposes. The ClamAV detection and ML classifier strongly suggest this PDF is malicious, likely serving as a lure for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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.ideaklinikbakirkoy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612dacc7af4e5---41186566323.pdf In PDF document text
    • https://stewsites.com/wp-content/plugins/super-forms/uploads/php/files/81fdabb2a67a7d722df06be3d481be9d/xojavegak.pdfIn PDF document text
    • http://okmarin.ru/userfiles/file/4010670913.pdfIn PDF document text
    • http://www.ximangsongthao.com.vn/app/webroot/uploads/files/lasaf.pdfIn PDF document text
    • https://vzglavniki.net/data/file/jomozezananokiwo.pdfIn PDF document text
    • http://dyweisheng.com/uploadfile/file/2021081708274173499.pdfIn PDF document text
    • https://deedpoll.sg/wp-content/plugins/super-forms/uploads/php/files/0ec466ac1a170804902ceb84df5410b9/livifiwotuwilifev.pdfIn PDF document text
    • http://americandeliorder.com/uploads/files/livexetasikugabixipuma.pdfIn PDF document text
    • http://prosquash.by/data/nenadunarafutape.pdfIn PDF document text
    • https://ewastexperts.com/userfiles/files/84574225745.pdfIn PDF document text
    • https://claphamjunction.com.au/wp-content/plugins/super-forms/uploads/php/files/ffbef4200ccb6cdaa3f455cf2f42b4c1/negag.pdfIn PDF document text
    • https://sitebyside.ru/wp-content/plugins/super-forms/uploads/php/files/4c4b474caa9fb7aaeafd528ba219e3a8/1153359867.pdfIn PDF document text
    • http://pospatrans.cz/UserFiles/File/90069259763.pdfIn PDF document text
    • http://kindervakantieweekdeurne.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16075c10c57732---81449819380.pdfIn PDF document text
    • http://cfacgroup.com/uploads/FCK_files/file/84478445981.pdfIn PDF document text
    • http://pajurioverslas.lt/ckfinder/userfiles/files/xupijorabipivit.pdfIn PDF document text
    • https://aulacvn.com/upload/fck/file/xeloparepakinivifuf.pdfIn PDF document text
    • http://insureavisitor.com/userfiles/file/60242597936.pdfIn PDF document text
    • http://thessalonikiflights.com/files/files/19855949247.pdfIn PDF document text
    • http://ambulatorioveterinarioilprato.eu/userfiles/files/19504456463.pdfIn PDF document text
    • http://ar-intl.net/wp-content/plugins/super-forms/uploads/php/files/7ghngfft5ppv2hno5p634jg0a4/38976948320.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=cisco+virl+tutorial+pdfPDF 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_off0000c905.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC905 10576 bytes
SHA-256: d74baf04f96a8649dd282db3e16bfa4dd1b35969218d2c8f80e5394eea8976aa
font_01_sfnt_off0000e159.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE159 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f96b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF96B 16568 bytes
SHA-256: 12bc7e4dff7a0240a5068d0d0c8a44499b66c209a578d021e086e7f1a343c0c3