Malicious PDF — malware analysis report

Static analysis result for SHA-256 f276fe8cfe0ebe26…

MALICIOUS

PDF

78.6 KB Created: 2021-07-12 22:45:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: e193903803ffebb2a4d29de2cadb248c SHA-1: 04c667e0aab73a266e8879267a517eaa4157b00e SHA-256: f276fe8cfe0ebe262c50b9e5480727e97a8ff4f2e84268c73e41274c6a0a546b
96 Risk Score

Malware Insights

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

The PDF file contains a large number of embedded URLs, many of which point to compromised WordPress sites. The ML classifier strongly indicates maliciousness. The primary function appears to be acting as a link farm, likely for SEO poisoning or to distribute further malicious content, rather than executing a direct exploit.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://ketgate.eu/wp-content/plugins/super-forms/uploads/php/files/e82fd2b3492f9fd26d03b0db98888212/1868997692.pdf In PDF document text
    • http://www.hollyskauaicondo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606fc0d3b0d9e---77139025903.pdfIn PDF document text
    • http://www.sarajevo-inn-grunewald.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b97cd32c61b---48460342177.pdfIn PDF document text
    • https://attack.lt/images/files/lipideselumumodopazapa.pdfIn PDF document text
    • http://www.rec39.ru/wp-content/plugins/super-forms/uploads/php/files/ce849e800d292ca79af72690b8ffb826/wozodexinavefozuta.pdfIn PDF document text
    • http://yule-sign.com/upload/editor/file/20210626091159.pdfIn PDF document text
    • http://broadviewlibrary.org/uploaded_bvlib/file/59964979598.pdfIn PDF document text
    • http://aleeblog.com/wp-content/plugins/super-forms/uploads/php/files/5g804gam2uk9u8khn3llfnnah0/wetojaveb.pdfIn PDF document text
    • https://www.toptalentusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f1f524f080---55397694867.pdfIn PDF document text
    • https://endoaccessories.com/wp-content/plugins/super-forms/uploads/php/files/v48h9e6n69ju1unl4ssp97h7ri/64867189264.pdfIn PDF document text
    • http://skisun.it/userfiles/files/figazubebi.pdfIn PDF document text
    • https://www.dishdivvy.com/wp-content/plugins/super-forms/uploads/php/files/e8bbbe2aba3f41f5bc23848ce4b70018/fibilipowudolibefe.pdfIn PDF document text
    • http://kemenyseprosiklos.hu/upload/file/48556318205.pdfIn PDF document text
    • http://okeefesreef.com/ckfinder/userfiles/files/59185307654.pdfIn PDF document text
    • https://123kozijnofferte.nl/wp-content/plugins/super-forms/uploads/php/files/a4sgjg36dd87ho4llp23snuue1/lujopazusakaluko.pdfIn PDF document text
    • http://futurepoolandspa.com/ckfinder/userfiles/files/lujodudonekoxatew.pdfIn PDF document text
    • https://husvagnsexpo.se/wp-content/plugins/formcraft/file-upload/server/content/files/160d6a364409ad---jefotetufosub.pdfIn PDF document text
    • http://ecohort.com/userfiles/files/pagisowemibeb.pdfIn PDF document text
    • http://agcslohian.com/userfiles/file/95197940620.pdfIn PDF document text
    • http://pebyte.com/wp-content/plugins/super-forms/uploads/php/files/fmh96vr6h6e7gpibr9cf9i8omb/98170161730.pdfIn PDF document text
    • http://sva-jeanroze.com/xmedia/file/60367131969.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=only+one+command+websitePDF 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_off0000d1a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD1A7 16588 bytes
SHA-256: 89230992dffcad2b07483adbb2a169ed38ee0e99ac89889681359327933d0edd
font_01_sfnt_off0000fcb8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFCB8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000114cf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x114CF 10796 bytes
SHA-256: 0acfb7d679b547e193cdea134d6a97044d2338bfc52e0efc6117a4c442a0cec3