Malicious PDF — malware analysis report

Static analysis result for SHA-256 b6e317b3459b819e…

MALICIOUS

PDF

83.5 KB Created: 2021-09-02 07:18:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 36ad50589212a3489fefa683fbf6be99 SHA-1: 75bfec73fa18fed6ec89df6f3d23d0c678558a17 SHA-256: b6e317b3459b819e59fe0b713941843a43663df5eb79b2d6b0f7ff02998041e3
96 Risk Score

Malware Insights

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

The PDF file was identified as malicious by an ML classifier and contains numerous embedded URLs. Many of these URLs point to compromised CMS uploads or disposable hosting, suggesting a link farm designed to redirect users to malicious sites. No scripts were extracted from this sample, and the document body was heavily obfuscated and truncated, preventing a deeper analysis of its specific lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://publicbridge.pl/userfiles/file/82972856945.pdf In PDF document text
    • http://flexa.cz/docs/file/34035977867.pdfIn PDF document text
    • https://nabil-doukali.com/userfiles/file/76995615097.pdfIn PDF document text
    • http://babywagen24.de/userfiles/file/17371994248.pdfIn PDF document text
    • https://giga-tronics.com/userfiles/files/fifupulaxaletuto.pdfIn PDF document text
    • https://gpagroup.in/wp-content/plugins/formcraft/file-upload/server/content/files/160bbac17c55be---bagomizinipizisun.pdfIn PDF document text
    • http://archi-m.ru/userfiles/file/xikos.pdfIn PDF document text
    • https://rittenhousesmiles.com/wp-content/plugins/super-forms/uploads/php/files/3e99b423194365d2f9397b5f33f51956/zuvanozuzezisinoj.pdfIn PDF document text
    • https://eyetracking.pl/userfiles/file/85717224092.pdfIn PDF document text
    • https://zop.bg/webroot/img/content/files/61644730314.pdfIn PDF document text
    • http://cukrarska-vyroba.cz/UserFiles/File/75864928709.pdfIn PDF document text
    • https://cubic.is/userfiles/file/72813255206.pdfIn PDF document text
    • http://asirius.su/wp-content/plugins/super-forms/uploads/php/files/f49eab044ffdeb9cfd7fb3ff23806852/19976483876.pdfIn PDF document text
    • https://hsegroup.ru/wp-content/plugins/super-forms/uploads/php/files/9mru3n7trdg03tsnipjce4cnh1/33583450039.pdfIn PDF document text
    • https://biserica-izvorul-tamaduirii.ro/files/degukulanofik.pdfIn PDF document text
    • http://kondicionery-dolgoprudny.ru/upload_picture/file/ridateniwajosutagojanofi.pdfIn PDF document text
    • http://paillasse.hu/userfiles/file/lixugunadubetowabo.pdfIn PDF document text
    • http://singer-island-condos.com/userfiles/files/21285193579.pdfIn PDF document text
    • http://www.opencalgary.org/wp-content/plugins/formcraft/file-upload/server/content/files/160d6f04cdd353---xixawijil.pdfIn PDF document text
    • http://blpest.com/UserFiles/file/56836365193.pdfIn PDF document text
    • https://yidinfo.net/wp-content/plugins/super-forms/uploads/php/files/4uidg6vjgo4aord7bispe3j7ml/sojixexuvewidowufipodejop.pdfIn PDF document text
    • http://hillcountryawningsandsunscreens.com/wp-content/plugins/formcraft/file-upload/server/content/files/160725b33cede6---xuvote.pdfIn PDF document text
    • http://alacarte-design.de/userfiles/file/molanazivu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=how+to+add+an+icloud+email+to+androidPDF 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_off0000e231.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE231 10540 bytes
SHA-256: b7eae7735d57d06a199a63b3093aa0df9933cf5035098863d9c06696cc9ff684
font_01_sfnt_off0000fa2a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA2A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001123c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1123C 17168 bytes
SHA-256: ef05754f17fdbebff0b0ddc66ea925bb1fe265579c241c05680c59146fd4d784