Malicious PDF — malware analysis report

Static analysis result for SHA-256 dcb0befb4c0ca752…

MALICIOUS

PDF

81.8 KB Created: 2021-09-05 17:27:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 944db249d3ef4c50f3f7e12932877814 SHA-1: d4d42f298e3301ec605b241cedbb43d4fea1aebe SHA-256: dcb0befb4c0ca752b0393876f061cd327779475c5b06c97b03fe5a46c6566380
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains a link farm pointing to multiple compromised websites, as indicated by the 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' heuristics. The ML classifier and ClamAV also flagged this PDF as malicious. The primary function appears to be directing users to potentially malicious content hosted on these compromised sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://harlit.com/upfiles/file/galojikilivom.pdf In PDF document text
    • http://nuyewpilot.academy/wp-content/plugins/super-forms/uploads/php/files/fde6f17ac8ddb43df584a92e80f9f383/boleluvaxufutovomibora.pdfIn PDF document text
    • https://alternativecarrepair.com/userfiles/file/87853010142.pdfIn PDF document text
    • https://djennebeads.com/nbloom/fckuploads/file/96866674420.pdfIn PDF document text
    • http://lirealestatelitigator.com/wp-content/plugins/super-forms/uploads/php/files/0b3bd04479ac6f9938d05e91dd1a85ca/tejigidokomufudan.pdfIn PDF document text
    • https://svarovanijelinek.cz/ckfinder/userfiles/files/35067733394.pdfIn PDF document text
    • https://acryl-bg.com/userfiles/file/jumetabibu.pdfIn PDF document text
    • https://autoprofi.ua/userfiles/file/dusagagugebifukeboj.pdfIn PDF document text
    • https://www.webplease.it/wp-content/plugins/super-forms/uploads/php/files/hpq9pvfku8330h09u73vbqsbnk/limisefojaritidodepuzakos.pdfIn PDF document text
    • http://e-hematologica.com/users//file/ruvawagenarixidebipexig.pdfIn PDF document text
    • https://micast.de/wp-content/plugins/super-forms/uploads/php/files/tnpksrh9r6ul5g35e9q0mdv894/lakatax.pdfIn PDF document text
    • http://taxplus.in/images/contentimages/files/40753290101.pdfIn PDF document text
    • http://principessavencanice.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c437c07234a---15731395337.pdfIn PDF document text
    • https://sssmri.com/ckfinder/userfiles/files/89982951870.pdfIn PDF document text
    • https://too.kg/wp-content/plugins/super-forms/uploads/php/files/3c61e57675f8aa9fcba9ea3b2b6761ef/45605767566.pdfIn PDF document text
    • http://thietbixanh.net/uploads/files/11097198154.pdfIn PDF document text
    • http://mfcwestenkwartier.nl/beta/userfiles/file/74787017944.pdfIn PDF document text
    • https://gobelsprofil.com/upload/files/kepadubilegadu.pdfIn PDF document text
    • http://contactconfiance.com/files/files/82332664407.pdfIn PDF document text
    • https://galedo.cz/www/data/cms_files/files/77393004216.pdfIn PDF document text
    • https://imagebrandstudio.com/userfiles/file/56333037870.pdfIn PDF document text
    • http://ridendo.cz/files/file/gedimo.pdfIn PDF document text
    • https://www.spreefahrten-berlin.de/wp-content/plugins/super-forms/uploads/php/files/484p4vjb48pcsfdk8005mj2nbe/37058610204.pdfIn PDF document text
    • http://phutunggiahungoto.com/uploads/files/69657493885.pdfIn PDF document text
    • https://dbmotorbrokers.com/userfiles/file/71475707690.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=reflective+symmetry+worksheets+with+answersPDF 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_off0000d983.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD983 11004 bytes
SHA-256: a13c1bf849c84f00e8f9d895f26172a04d64a5c54c87d3b59094b76ba6492e24
font_01_sfnt_off0000f2fa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2FA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010b0c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B0C 18080 bytes
SHA-256: ed5c2f83d77955072caa7ea06868e6f9d8c0ce468c3bb15a684d714ccb26664b