Malicious PDF — malware analysis report

Static analysis result for SHA-256 c40b8e14917a32c3…

MALICIOUS

PDF

82.8 KB Created: 2021-08-29 08:50:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: e54b4930cbedcf86ed229b1b0090b980 SHA-1: d2401e40b37fbda086250c35a9272b284ef766d4 SHA-256: c40b8e14917a32c351d5ea27782441723313a4e10640658cc2858ad4246431e3
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to multiple compromised WordPress sites, identified by heuristics like 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' and 'PDF_SEO_DISPOSABLE_LINK_FARM'. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution via these links. No scripts were extracted, and the document body was unreadable binary data.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://kodeac.com/wp-content/plugins/super-forms/uploads/php/files/rm5hq2ps6cdojrkgrn4lrbkne3/75524210867.pdf In PDF document text
    • https://tripleccompanies.com/wp-content/plugins/super-forms/uploads/php/files/e494be33cc1c5d23615766355c6f34aa/wekolimatexesome.pdfIn PDF document text
    • https://akdenizokullari.k12.tr/wp-content/plugins/super-forms/uploads/php/files/fk79hl8blbqt6p4qgs0lliaetc/jovibamuki.pdfIn PDF document text
    • http://fabrykakonwersji.pl/wp-content/plugins/super-forms/uploads/php/files/9ee7700b8f03c1f8920ce4412466a9cd/77984756438.pdfIn PDF document text
    • http://mognational.com/wp-content/plugins/formcraft/file-upload/server/content/files/16081f938c30f6---73931423610.pdfIn PDF document text
    • http://fkjz.cn/upload/files/2021/07/202107191548592925.pdfIn PDF document text
    • http://alvasari.com/wp-content/plugins/formcraft/file-upload/server/content/files/160805ac8729db---vexogadofatazuwe.pdfIn PDF document text
    • http://shmountaineering.co.uk/wp-content/plugins/super-forms/uploads/php/files/tksi3uq2vh60mad1vq7h8lhf14/mapijemupozituxiwo.pdfIn PDF document text
    • http://cohn-vossen.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f42b218628---78877221573.pdfIn PDF document text
    • http://www.julitolaschools.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b64cb8ac022---pokikodana.pdfIn PDF document text
    • https://ailani.org/wp-content/plugins/super-forms/uploads/php/files/77de00e901b6db1ac182f881b874defe/wezomipamumitijibi.pdfIn PDF document text
    • https://www.mmgrowersg.com/ckfinder/userfiles/files/poxefuzenufatixew.pdfIn PDF document text
    • https://balance-global.com/wp-content/plugins/super-forms/uploads/php/files/4uiq21mfqfnkvl25fgmdv262p6/sizukovejikozase.pdfIn PDF document text
    • http://teaandtiarasottawa.com/clients/e/e8/e8f54e69a7463df9fd0adff13cd8e90f/File/mijowon.pdfIn PDF document text
    • https://123kozijnofferte.nl/wp-content/plugins/super-forms/uploads/php/files/4bj2oa2vhace4id2ka1b4ucgc2/52283315017.pdfIn PDF document text
    • https://www.darrellstuckey.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a70b2db6406---jibizujikojuro.pdfIn PDF document text
    • http://kingspec.su/wp-content/plugins/super-forms/uploads/php/files/hm5i2hjju4sf9qrb6ec347q6ad/gulodenig.pdfIn PDF document text
    • https://sunrise-photon.com/upfiles/editor/files/17105869902.pdfIn PDF document text
    • http://cecev.com/stockages/files/15200453953.pdfIn PDF document text
    • https://hashtag.school/userfiles/file/46989886926.pdfIn PDF document text
    • http://www.recetasyconsejos.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b2807d97a3d---85960150016.pdfIn PDF document text
    • https://afriqueitnews.com/wp-content/plugins/super-forms/uploads/php/files/25b6bf5de9ecad4fe08b0e3d593ad2c3/49067454663.pdfIn PDF document text
    • http://leinerpakgelatine.com/survey/userfiles/files/razumovebadilodokej.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=how+to+fly+in+minecraft+in+pcPDF 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_off0000de20.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE20 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f632.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF632 18332 bytes
SHA-256: dcabfdea3dd44a17d0942ef625b993a89e3ac3662063826bea8f3ee90dbf54c4
font_02_sfnt_off0001256e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1256E 10664 bytes
SHA-256: 06c7227c2411a7922abfe6fef9ce361e27de5460cb0e68e0fd97874598aeb292