Malicious PDF — malware analysis report

Static analysis result for SHA-256 fb88e5fe436d9ce6…

MALICIOUS

PDF

85.2 KB Created: 2021-09-17 17:46:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: bfa83b4cff968f0b18409e0ef2d62e77 SHA-1: a6020d2fe7b7ca172fc7cae7478cc465652390ac SHA-256: fb88e5fe436d9ce6ff6a39bfc1f00504bb4699314d6bd0bd1dc75292fcb5f27e
96 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs that function as a link farm, with several pointing to compromised WordPress sites. The ML classifier strongly indicated maliciousness, and the presence of a link farm on disposable hosting suggests an attempt to distribute or redirect users to malicious content. No scripts were extracted, but the overall structure and URL distribution are indicative of a malicious campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9905

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://crewmak.ru/uplcv?utm_term=android+football+games+with+controller+support PDF link annotation
    • https://tumsad.org/img/editor/image/file/gipok.pdfIn PDF document text
    • http://www.egymast-segito.hu/uploaded/fck/file/23446588021.pdfIn PDF document text
    • http://airfa.it/userfiles/file/66757052204.pdfIn PDF document text
    • http://greenmodels.ru/uploads/files/lizoxijuwijuvofunepid.pdfIn PDF document text
    • http://www.cpnatacao.pt/backoffice/ckfinder/userfiles/files/15044642679.pdfIn PDF document text
    • https://kungfuclasshongkong.com/louis/taichi/ckfinder/userfiles/files/58205731617.pdfIn PDF document text
    • http://niszczeniewaw.pl/userfiles/file/penopikajataxaxurasinonur.pdfIn PDF document text
    • http://www.peritaonline.es/ckfinder/userfiles/files/65904497445.pdfIn PDF document text
    • https://amesmedicalservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139814550554---15381995114.pdfIn PDF document text
    • http://www.musicmaestrodiscos.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1612f6df4f4138---momuzizelaxonaveropemazad.pdfIn PDF document text
    • https://414movement.com/wp-content/plugins/super-forms/uploads/php/files/8eda603be0780765d7bfbda8e061d023/12196725665.pdfIn PDF document text
    • http://quetthe.com/upload/files/tedokejarifevasaf.pdfIn PDF document text
    • https://hamzakocakoglu.com/userfiles/file/siguvasatilufofa.pdfIn PDF document text
    • http://phutungotodungha.com/img/files/pijovijuborudukan.pdfIn PDF document text
    • http://vako.vn/app/webroot/uploads/files/40068961721.pdfIn PDF document text
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/bl6815kagg1ofbogo7jgtp76g0/basipomigupux.pdfIn PDF document text
    • http://sarica.com.tr/ckfinder/userfiles/files/28278577840.pdfIn PDF document text
    • http://rqconsultores.com/userfiles/file/rijabuzirivorisi.pdfIn PDF document text
    • http://onthebroadway.com/CPD/adminpanel/upload/file/wemajamomimimibeva.pdfIn PDF document text
    • http://ntep2008.com/UserFiles/File/57892782544.pdfIn PDF document text
    • http://kevinmcallisterlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/58704213420.pdfIn PDF document text
    • http://khaskhaan.mn/uploads/userfiles/files/vupalekajug.pdfIn PDF document text
    • http://bestforfishing.com/wp-content/plugins/super-forms/uploads/php/files/4f5e60752623030c4fecba4422f63603/daborewegivenezodivamam.pdfIn PDF document text
    • http://jullien38.com/ressource/site-image/files/91258504808.pdfIn PDF document text
    • http://robotsuk.com/luckingbros.co.uk/userfiles/files/10154999252.pdfIn PDF document text
    • http://bbmeti.it/userfiles/files/regazoruvokurarumapexamul.pdfIn PDF document text
    • https://defi128.phpascal.com/userfiles/files/wisud.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_off0000e93b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE93B 11376 bytes
SHA-256: fc38541d8a1677ec3f088aeab9ce2f4c433f540dcef058c4f2079daf7c115ffc
font_01_sfnt_off0001037f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1037F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011b91.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B91 16700 bytes
SHA-256: 1d0c1f93b5996540a50593102730e2e988d16d7b671c0d34e273dbba7ad6343f