Malicious PDF — malware analysis report

Static analysis result for SHA-256 8c4b92be397e8fe8…

MALICIOUS

PDF

83.7 KB Created: 2021-08-28 19:01:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-04
MD5: 85268a2715eca0c022c8ced26619d818 SHA-1: dbe5ea2941eb7ada2bc8ab0d9e189a27f678f572 SHA-256: 8c4b92be397e8fe8cadb2f7cee8cefe357c69d5cb9d34454f54f7892a084aeef
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9909

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 https://nomylo.ru/uplcv?utm_term=carl+lewis+mike+powell PDF link annotation
    • https://kompaspt2.com/contents//files/mofebas.pdfIn PDF document text
    • https://cullinanconstruction.com/wp-content/plugins/super-forms/uploads/php/files/i1lfin7q3pips62t44rj0cvpua/41943059418.pdfIn PDF document text
    • https://kalatranslation.co.uk/wp-content/plugins/super-forms/uploads/php/files/j1d8qogqtmv9casgdho6aem717/mogone.pdfIn PDF document text
    • https://pikewallis.no/wp-content/plugins/formcraft/file-upload/server/content/files/160bd85cc34d30---44539739859.pdfIn PDF document text
    • https://www.sevgiliyevideo.net/wp-content/plugins/formcraft/file-upload/server/content/files/16087fb925727c---78730789396.pdfIn PDF document text
    • http://inventory-acepipe.com/images/uploads/files/delemiwar.pdfIn PDF document text
    • http://www.psstrecno.sk/wp-content/plugins/formcraft/file-upload/server/content/files/160c0e205d8efe---42410169831.pdfIn PDF document text
    • https://www.stamfordtaxis.com/wp-content/plugins/super-forms/uploads/php/files/4umbq473l257r5f6ttf2b7olfe/bosipokidifejulofaneg.pdfIn PDF document text
    • http://uelzecht.lu/userfiles/files/selekiboza.pdfIn PDF document text
    • http://sghscsjamarai.org/guruhargobind/userfiles/file/mojomudisefevolufigivuv.pdfIn PDF document text
    • http://saconsultancy.com/userfiles/file/89420409369.pdfIn PDF document text
    • https://vivaldiroberto.com/img/files/mediafiles/file/604894128.pdfIn PDF document text
    • http://kanalprofi.at/UserFiles/file/38836701262.pdfIn PDF document text
    • http://nowyhotelik.pl/userfiles/file/dibumuvekubox.pdfIn PDF document text
    • https://aldea.work/wp-content/plugins/super-forms/uploads/php/files/70dec76bd9beb305d39558880d18091c/guduborajalef.pdfIn PDF document text
    • https://greshamgilessalon.com/wp-content/plugins/super-forms/uploads/php/files/a1c97f1c07fdcad908f36cf71a3a60a1/83156005983.pdfIn PDF document text
    • http://www.gaviprintpack.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609deb8a04e66---58973605345.pdfIn PDF document text
    • http://lifemartrealestateconnect.com/wp-content/plugins/super-forms/uploads/php/files/qlj4pb739q5k7fn6oed212m4q4/tesanatitiro.pdfIn PDF document text
    • https://sipare.com.ar/wp-content/plugins/super-forms/uploads/php/files/0ve81gorqe45e05r3v5vv4tpvk/35220016493.pdfIn PDF document text
    • http://candientuvibra.com/images/file/bifirigaxuworo.pdfIn PDF document text
    • https://ymy-tea.tw/upload/files/gugobajol.pdfIn PDF document text
    • https://doctmcooper.com/userfiles/files/15874153182.pdfIn PDF document text
    • http://globalroomplus.com/bot/ckfinder/uf/files/91941571620.pdfIn PDF document text
    • http://nirmalamathachurch.org/cms_uploads/image/file/73478040377.pdfIn PDF document text
    • http://primaria-ciocirlia.ro/media/file/kewanenisuxavogin.pdfIn PDF document text
    • https://kmkmekanik.com/upload/ckfinder/files/22849293574.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_off0000e207.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE207 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fa19.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA19 17708 bytes
SHA-256: efa32d2884b647d43e186c6f0bc4425fe1e577c3fea511f981f6ed37ed9dffde
font_02_sfnt_off0001283c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1283C 10420 bytes
SHA-256: 33186c0b7344d90d3b134ece231e4bdb69c24442c68f30f506e49724a378bb4b