Malicious PDF — malware analysis report

Static analysis result for SHA-256 185207831e22d5db…

MALICIOUS

PDF

69.7 KB Created: 2021-09-16 01:53:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: c57dec2ab8b15999e80c06476053c78b SHA-1: 95bc3ad8021a752bc4cde9e7f1c52b8d802b767b SHA-256: 185207831e22d5db5ee3bdea5eaccf574900129781a5a366a55b3e3c787ee2fb
96 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many pointing to disposable hosting or compromised CMS upload directories, indicating a link farm designed to redirect users to malicious sites. The ML classifier strongly flagged this PDF as malicious, supporting the conclusion that it is used for phishing or malware distribution. No scripts were extracted, but the primary attack vector appears to be the exploitation of user trust through deceptive links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9849

Heuristics 5

  • 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://synerhu.ru/uplcv?utm_term=play+store+keeps+pending PDF link annotation
    • http://fmafirm.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/69730098239.pdfIn PDF document text
    • http://sevoir.hu/uploads/file/xaxuxejagivenunajomidu.pdfIn PDF document text
    • http://harc-ias.vn/Images_upload/files/mifazuwo.pdfIn PDF document text
    • https://khonggiansangtao.com/platformecom/img/upload/file/82932362926.pdfIn PDF document text
    • https://www.inkfactory.pk/wp-content/plugins/formcraft/file-upload/server/content/files/1613fe2e77fd24---3958127119.pdfIn PDF document text
    • https://tylbm.com/Upload/ckeditor/files/tutowedodurezimegoripa.pdfIn PDF document text
    • http://ubestsports.com/imager/files/20210908085501.pdfIn PDF document text
    • http://studiovalentini.eu/userfiles/files/85419601448.pdfIn PDF document text
    • http://dalnoboy.net/data/filestorage/upload/files/44415595734.pdfIn PDF document text
    • https://senzedigicraft.com/wp-content/plugins/super-forms/uploads/php/files/3eb90d539d1fc75b8dac6b7955a3bd96/53092960930.pdfIn PDF document text
    • http://pokrowce-ochronne.pl/Upload/file/39379043309.pdfIn PDF document text
    • https://listapp.in/ci/userfiles/files/fasupisunamoleje.pdfIn PDF document text
    • http://qwerty.pl/_data/file/dozeketikaraxu.pdfIn PDF document text
    • http://18554080.com/userfiles/file/99016265497.pdfIn PDF document text
    • http://electrogalicia.com/electrogalicia/recursos/archivos/weleliduwipumebezujovubub.pdfIn PDF document text
    • https://oncallanatomist.com/ckfinder/userfiles/files/kasemenimaj.pdfIn PDF document text
    • http://pk.mo/userfiles/file/renudimilumirerorek.pdfIn PDF document text
    • https://pluviaterra.mx/wp-content/plugins/super-forms/uploads/php/files/3383aa0d5efcb833dce067bc42ef4569/jomekonevuvawuwa.pdfIn PDF document text
    • http://polins.org/public/userfiles/file/87538915258.pdfIn PDF document text
    • https://elitteaccesorios.com/wp-content/plugins/super-forms/uploads/php/files/jku7ekkvgqseihpnbekp1a7n9p/87228690396.pdfIn PDF document text
    • http://daimarconstrucciones.com/images/admin/file/49958524660.pdfIn PDF document text
    • http://mrtowing.ca/Lawyers/userfiles/file/penilanexunizebinedim.pdfIn PDF document text
    • http://agataklimowska.pl/userfiles/file/17801977853.pdfIn PDF document text
    • https://ville-saintleonard.fr/pdf/37733541686.pdfIn PDF document text
    • http://snap-drone.com/userfiles/file/numagel.pdfIn PDF document text
    • https://aviseco.ro/userfiles/file/tewuwepaniwimujapagaturi.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_off0000b29b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB29B 10772 bytes
SHA-256: 1ebb60caa3726bb4714ed106edfc56844c6aa4768c99b3933573e46079a40c93
font_01_sfnt_off0000cb5f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB5F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e371.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE371 15080 bytes
SHA-256: e80480a8255b5aa5a79f3963e9bcd12772c497824d857459ea6a1f2a0b9b3486