Malicious PDF — malware analysis report

Static analysis result for SHA-256 b5a83919df2cc220…

MALICIOUS

PDF

82.2 KB Created: 2021-09-06 18:35:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: fec0fa7e02a55e4a73e11edaa2f6e99c SHA-1: 0c57c367be99be89bd69ad07008d10e21219e02c SHA-256: b5a83919df2cc2206a2b035d177b6ddae607410a8650cda755fd3af6826ebaaa
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable domains. These links are likely intended to redirect users to malicious content or facilitate SEO spam. The ML classifier strongly indicated maliciousness, supporting the assessment of a link farm attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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://adbetelparaguay.com/wp-content/plugins/super-forms/uploads/php/files/27b2853371e829fda5820108ef1c9eb8/legodasosuvamiwuzoz.pdf In PDF document text
    • https://amalighting.com/wp-content/plugins/super-forms/uploads/php/files/c64ddd27bdb47e03468d7ea688fff7aa/mujuzafafenipusetazojo.pdfIn PDF document text
    • https://sckstone.com/wp-content/plugins/super-forms/uploads/php/files/24ea5e41dc2450cd43b0013ff59082df/titiruwibone.pdfIn PDF document text
    • http://www.onekaddy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c0b29110f9f---vavodo.pdfIn PDF document text
    • http://diamant-x.sk/UserFiles/file/67447855345.pdfIn PDF document text
    • https://cornerstonelaw.eu/userfiles//file/diraso.pdfIn PDF document text
    • https://www.ideaklinikbursa.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d9f749a441---dopimigevevikewalovuramo.pdfIn PDF document text
    • http://songdolandmarkcity.com/userfiles/file/16032826261.pdfIn PDF document text
    • http://siripanyalamphun.com/user_img/files/15413445906.pdfIn PDF document text
    • http://artospace.com/pics/file/donidifamadakijuvosotodeg.pdfIn PDF document text
    • http://pkpneu.cz/userfiles/file/wenako.pdfIn PDF document text
    • http://www.etoiles-recrutement.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087d7aae8576---kafibemaxujedotimuw.pdfIn PDF document text
    • https://www.americansummercamps.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075c52206624---jivikavenizu.pdfIn PDF document text
    • http://zonazero.es/userfiles/file/20182138977.pdfIn PDF document text
    • http://salonlomi.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160a24dcc5caa4---kofepurenuso.pdfIn PDF document text
    • http://www.combatsim.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160ba50d76300d---44384605400.pdfIn PDF document text
    • https://gmonlinestore.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608fe4caadc9b---93865040513.pdfIn PDF document text
    • http://www.horakgolf.cz/ckfinder/userfiles/files/zatejevebusexomexevejoga.pdfIn PDF document text
    • http://anthonyjcincottalaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/nubofalokizafiv.pdfIn PDF document text
    • http://radfordhsclassof1970.com/clients/878146/File/7432338976.pdfIn PDF document text
    • http://toeicspeaking.net/_UploadFile/Images/file/27406913545.pdfIn PDF document text
    • https://bluebeakbranding.com/wp-content/plugins/super-forms/uploads/php/files/48123b1769a0ea9648fbe61f5bbdd6d7/40629463396.pdfIn PDF document text
    • http://www.alex-vasilkov.ru/images/wisdom/file/3758903261.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=four+goals+of+psychology+pdfPDF 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_off0000dd5a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD5A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f571.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF571 10664 bytes
SHA-256: 3420c22c98957ce390ece9dca3940a47782e7e92bdb42e0add4f426ca7c0baf7
font_02_sfnt_off00010dce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10DCE 17816 bytes
SHA-256: 813a698ae9374e1b1cb309d4a87110b3931e370bfb8ab4f6be7a5ebc181723a0