Malicious PDF — malware analysis report

Static analysis result for SHA-256 9e994c7c30069bc8…

MALICIOUS

PDF

76.1 KB Created: 2021-09-06 20:38:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-02
MD5: 9f1a948aee559dc62fc6ad2b03ec80a9 SHA-1: 9b01fdcd2f6b00684fe4b4f89eafc4b86c319155 SHA-256: 9e994c7c30069bc89f711d0fff75adc16fddd4fbb7790fe4fa94f007ef05a726
96 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by 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 0.9973

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://catamma.ru/uplcv?utm_term=hardy+weinberg+problems+worksheet PDF link annotation
    • http://etnorom.hu/pictures/pamadododipakofamirowajo.pdfIn PDF document text
    • http://msmzizkov.cz/data/dokumenty/99885440338.pdfIn PDF document text
    • http://mweb.cz/images/file/xovokud.pdfIn PDF document text
    • http://www.sunaryem.com.tr/wp-content/plugins/super-forms/uploads/php/files/6l43f6ui2c4kjlmeu3qcnsqa06/8244776142.pdfIn PDF document text
    • http://kino-profi.com/wp-content/plugins/super-forms/uploads/php/files/6147e358397e3f1ca2b8ec17eb704334/84674824646.pdfIn PDF document text
    • https://www.golddustdental.com/wp-content/plugins/formcraft/file-upload/server/content/files/1611b7575271cc---1313967149.pdfIn PDF document text
    • http://bumsnab.ru/uploads/files/11302766074.pdfIn PDF document text
    • http://robalton.es/Albums/images/file///vobazilafemop.pdfIn PDF document text
    • http://uniondeautoescuelas.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609118c212e07---60393946626.pdfIn PDF document text
    • http://ues-rb.ru/themes/ues-rb.ru/files/43689747740.pdfIn PDF document text
    • https://ag-concept.ru/wp-content/plugins/super-forms/uploads/php/files/2dbeefe6bee220cc47c93886d04c0474/91119007089.pdfIn PDF document text
    • https://smartcirclegroup.com/userfiles/file/97202492306.pdfIn PDF document text
    • https://monarchwinemerchants.com/wp-content/plugins/super-forms/uploads/php/files/b1cb927fbb2a2746fe2a4f5d613a5a14/xesapoxixitikum.pdfIn PDF document text
    • http://wernersuarez.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/jusemifenefoje.pdfIn PDF document text
    • https://gk-termopanel.ru/wp-content/plugins/super-forms/uploads/php/files/213f95ce4872e85700f3283ba6d782d1/legapumenudumirodepetum.pdfIn PDF document text
    • http://polipadel.com/userfiles/file/89112402209.pdfIn PDF document text
    • http://ngor2-3.com/file_media/file_image/file/2056893923.pdfIn PDF document text
    • http://yongqingtech.com/d/files/50494118782.pdfIn PDF document text
    • https://nuregio.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606d5fd60af39---33804317401.pdfIn PDF document text
    • https://webmenuplus.com/images/file/46783704831.pdfIn PDF document text
    • https://baconbites.com/wp-content/plugins/super-forms/uploads/php/files/bdh1gc79j6le46s1th6dl19qb1/wuragaven.pdfIn PDF document text
    • http://stolizstekla.ru/userfiles/file/9341734665.pdfIn PDF document text
    • http://kfnmsz.com/upfolder/e/files/20210817042031.pdfIn PDF document text
    • https://sasalidayanisma.org/uploads/file/rebevuvonaporisadotifi.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_off0000c3fd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC3FD 17352 bytes
SHA-256: 86bf6bd8a67198c175a4c56996034a2dfc4645cf5a467ca12ff01072823c0bb0
font_01_sfnt_off0000f0b1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0B1 11260 bytes
SHA-256: 6d9d920d4b9557c404052fc15405d038c32875815750ffd37eeb156250b76b0a
font_02_sfnt_off00010a79.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A79 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1