Malicious PDF — malware analysis report

Static analysis result for SHA-256 221f3df2e95efdaf…

MALICIOUS

PDF

77.4 KB Created: 2021-10-06 09:54:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: fb0c77470ac78f81f38f9d7dba90b448 SHA-1: 8475bf8549a204dfd438d3509e94c76c3c909d96 SHA-256: 221f3df2e95efdaf907ae778e77831b5709b429624de6211a000e9d775ca004e
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs pointing to external websites, many of which are hosted on compromised CMS platforms or disposable domains. The ML classifier strongly indicates malicious intent, and the structure suggests a link farm designed to redirect users to potentially harmful content. No scripts were extracted, but the overall pattern is consistent with a phishing or malware distribution lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://smidgel.ru/uplcv?utm_term=mmid+in+bank PDF link annotation
    • https://aviseco.ro/userfiles/file/xesanomususojuduwaji.pdfIn PDF document text
    • https://rcvizovice.cz/ckfinder/userfiles/files/nuganimupizuxu.pdfIn PDF document text
    • https://expungemyrecordnj.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b048f01f4e---sovomimoposomexefakodera.pdfIn PDF document text
    • http://radiosalsa.fr/php/rs/filesupload/file/69529488927.pdfIn PDF document text
    • https://sieseam.org/userfiles/files/24554071111.pdfIn PDF document text
    • https://cryptobasics.biz/uploads/files/45558797556.pdfIn PDF document text
    • http://criminisiepartners.it/userfiles/files/63904128711.pdfIn PDF document text
    • http://opsir.eu/files/file/12088586451.pdfIn PDF document text
    • http://pokorny-podlahy.cz/UserFiles/File/83982862959.pdfIn PDF document text
    • https://www.businesswatchguardingservices.co.uk/wp-content/plugins/super-forms/uploads/php/files/5d078fniq8h1kdesmee0equ4la/96121741263.pdfIn PDF document text
    • https://pmo.jot-solutions.com/files/kebuwigivevixitolaxufi.pdfIn PDF document text
    • https://www.web2business.pt/wp-content/plugins/formcraft/file-upload/server/content/files/16149cd02c4baa---butilup.pdfIn PDF document text
    • http://ristoranteyuri2.com/userfiles/file/soxojejatusagomudeweno.pdfIn PDF document text
    • http://neboskreb-irk.ru/uploads/userfiles/files/nonig.pdfIn PDF document text
    • https://girisimhaber.com/uploads/file/batiwipomubonamadak.pdfIn PDF document text
    • http://dinskayarealty.ru/media/file/3426492802.pdfIn PDF document text
    • http://studiolorenzino.eu/userfiles/files/rilagolirenuzeragivus.pdfIn PDF document text
    • http://hydrem.ru/images/file/lonomoruzuxetexago.pdfIn PDF document text
    • http://csc0851.com/userfiles/file/20210927163643_8r0jsk.pdfIn PDF document text
    • https://vgi-vn.vn/app/webroot/img/files/86746617011.pdfIn PDF document text
    • http://pk.mo/userfiles/file/dotezejufukagefa.pdfIn PDF document text
    • https://yourtuscanyguide.com/wp-content/plugins/super-forms/uploads/php/files/sahfbl1fivllvdbffdm6sofpr7/29391574875.pdfIn PDF document text
    • https://sunridgecorp.com/uploads/files/202109181031081103.pdfIn PDF document text
    • http://auxerretv.com/content/public/file/15829041772.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_off0000cae1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCAE1 18300 bytes
SHA-256: 2d6dd4bb8b3c62dc340963aac7517be81acf161dcb29c3b422bf02c0416e518f
font_01_sfnt_off0000f9fa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9FA 9972 bytes
SHA-256: 4b02d2953415212da3607a6d6a840b09781ab269fd41ad2486ed98153ea264a8
font_02_sfnt_off00010fed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10FED 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1