Malicious PDF — malware analysis report

Static analysis result for SHA-256 c0a0e508c7e7a865…

MALICIOUS

PDF

74.6 KB Created: 2021-09-04 19:27:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 3cc4cc0607c0c2351c4a215a9db70d22 SHA-1: 072544cc82a0914ed34839113bb8796d0c1e5132 SHA-256: c0a0e508c7e7a865cbd2ea7be8890cc3aba65bb86faf8ef3fd1b2cb5ddf5ac86
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous embedded URLs that function as a link farm, directing users to potentially compromised websites or malware hosting. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' suggests these links are designed for SEO manipulation or to distribute payloads, and the 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' indicates links pointing to compromised WordPress installations.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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://wastran.ru/uplcv?utm_term=add+subtract+fractions+word+problems+worksheet PDF link annotation
    • https://gservicepz.com/wp-content/plugins/super-forms/uploads/php/files/43aa3972b84914688f58a9fcaf750909/buxinudigawisefebanof.pdfIn PDF document text
    • https://belgradenightlife.info/wp-content/plugins/super-forms/uploads/php/files/udf9ilopq3e0a95k6r3p6865fh/mimanujawelegitixexaj.pdfIn PDF document text
    • https://euroroma-bg.org/files/file/fisawevu.pdfIn PDF document text
    • http://doyen.cc/images/upload/File/26430889590.pdfIn PDF document text
    • https://aynadakikemalizm.com/resimler/files/93397091070.pdfIn PDF document text
    • https://www.psalighting.com/wp-content/plugins/super-forms/uploads/php/files/ea44e53a6f03ee83d5615c823809e1ae/viserejikazajexaz.pdfIn PDF document text
    • http://www.supair-lux.hu/ckfinder/userfiles/files/24482889450.pdfIn PDF document text
    • https://serka.com/serka/upload/files/89559294127.pdfIn PDF document text
    • https://confidence-ist.mktechsol.com/ckfinder/userfiles/files/12066776621.pdfIn PDF document text
    • http://tokstar.com/_UploadFile/Images/file/72313554130.pdfIn PDF document text
    • https://eduinfinite.com/wp-content/plugins/super-forms/uploads/php/files/e995ac8ba5ae3f0870ba8b8e8408fa7d/95162383429.pdfIn PDF document text
    • http://www.franklinwebdesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a4d254e6818---2843993842.pdfIn PDF document text
    • http://quatanggiabao.com/images/uploads/files/38451911364.pdfIn PDF document text
    • https://autoroman-service.ro/imagini_ws/3081185052.pdfIn PDF document text
    • http://crabandclaw.com/uploads/files/tojepusupojijipa.pdfIn PDF document text
    • http://sieckultury.pl/wp-content/plugins/super-forms/uploads/php/files/47266adcd71060af3940dbc399a84d89/1938224674.pdfIn PDF document text
    • http://churchliferesources.org/wp-content/plugins/formcraft/file-upload/server/content/files/160754a38699bc---63857187269.pdfIn PDF document text
    • https://www.geosuiteonline.de/wp-content/plugins/formcraft/file-upload/server/content/files/16073004d2c0db---fegaxadik.pdfIn PDF document text
    • http://babamoleskine.com/files/file/jexarunedopot.pdfIn PDF document text
    • https://paklya.su/design/img/upload/file/vabiwabudopegomizotex.pdfIn PDF document text
    • http://domgr11.ru/uploads/files/86904509910.pdfIn PDF document text
    • http://mdbim.pl/ubezpiecz/obrazy/file/77064335736.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_off0000be8a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBE8A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d6a1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD6A1 11284 bytes
SHA-256: d0b1ae5b6ffbc79452e4d4adb1440d3deb5d7954bf1620c4b762a803db9df7ef
font_02_sfnt_off0000f0c5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0C5 16996 bytes
SHA-256: 7251c5cae1d17129b29d9fac542b709540e645b634a4f53890ce90f9f5860564