Malicious PDF — malware analysis report

Static analysis result for SHA-256 403c82e4c71b2761…

MALICIOUS

PDF

82.9 KB Created: 2021-09-10 08:13:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 801c5e4243e4b6764778525d35ebb85e SHA-1: 19880d2c86cca83b884a25031c868acbe42d86e9 SHA-256: 403c82e4c71b2761b261e7dec21b67bb1b76142790e8caa0f2123eb6c7140ed6
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, indicating a phishing or trojan payload. It contains numerous embedded URLs, many pointing to compromised CMS upload directories or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of external URI heuristics further supports the malicious redirection attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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 http://hytechplus.com/userfiles/file/58294653480.pdf In PDF document text
    • https://adepotcustom.com/UploadFiles/file/20210907135102189.pdfIn PDF document text
    • http://aloisiquadri.it/userfiles/files/wovupatekoxalobedugazul.pdfIn PDF document text
    • http://salocchi.it/userfiles/files/50095194611.pdfIn PDF document text
    • http://telek-trans.hu/editor_up/zojedipofafepezo.pdfIn PDF document text
    • http://dochoiotovn.com/uploads/userfiles/file/tojozukugeku.pdfIn PDF document text
    • https://www.lavishlook.se/wp-content/plugins/super-forms/uploads/php/files/95bd635d590e2fa5abd35f27cfca6c08/bojedatapusibabi.pdfIn PDF document text
    • http://randoquad72.fr/userfiles/file/34311464654.pdfIn PDF document text
    • https://girisimhaber.com/uploads/file/kesamogapu.pdfIn PDF document text
    • https://massagetheory.ca/wp-content/plugins/super-forms/uploads/php/files/e63e5bd84088769be88d2930bb498da6/50115913839.pdfIn PDF document text
    • http://www.schule.havonix.com/ckfinder/userfiles/files/52492772479.pdfIn PDF document text
    • http://boxerdapolenta.com/cmsimple/images/file/55770445337.pdfIn PDF document text
    • http://chukgoobok.com/files/fckeditor/file/60653732513.pdfIn PDF document text
    • http://fc-junajted.com/upload/datoteke/nosomumokowabevodewer.pdfIn PDF document text
    • https://derfo.info/resimler/files/kifamafezuvigi.pdfIn PDF document text
    • https://toananhmedical.com/uploads/files/sexarivemisaxogavob.pdfIn PDF document text
    • https://trucraftsmanship.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135284670d26---399697626.pdfIn PDF document text
    • https://dovolena-jiznicechy.cz/uploads/monikivifusikutizol.pdfIn PDF document text
    • https://aiwatopup.com/ckfinder/userfiles/files/67077346962.pdfIn PDF document text
    • http://aeon-dev.com/uploads/files/202109080702321149.pdfIn PDF document text
    • http://sculecuacumulator.ro/app/webroot/files/userfiles/files/wiwuxalulovodidep.pdfIn PDF document text
    • http://irths.com/upload_files/files/rafosokobuxe.pdfIn PDF document text
    • http://zamel2.pl/userfiles/file/42702978191.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=sharkboy+et+lavagirl+streaming+vfPDF 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_off0000db19.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB19 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f32b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF32B 18704 bytes
SHA-256: 0dbf6d82c74d66527228584061b17f27b7e405db62db75bcf17dfe6aaf09d4da
font_02_sfnt_off000123d5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x123D5 11148 bytes
SHA-256: 1e8c5b5545f0db3bc9a54ae2fe5c4af99420de0d44d210d06394e2b19c6bff9e