Malicious PDF — malware analysis report

Static analysis result for SHA-256 f22981ac7a196fbf…

MALICIOUS

PDF

92.4 KB Created: 2021-08-01 10:00:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 3ae28cf92c0105d49f67bd4368df4a4a SHA-1: 06223307298ee9b2c0fafac96896fa646ca8f633 SHA-256: f22981ac7a196fbfd5030f61999737060d570821fc7b45b397a7e75f233d726f
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 or other disposable hosting. The ML classifier strongly indicates maliciousness, and the heuristic firings suggest this PDF is a link farm designed to redirect users to potentially malicious content or for SEO manipulation. No scripts were extracted, but the primary attack pattern involves directing users to external, compromised resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9989

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://crysiq.ru/uplcv?utm_term=prensa+tijolo+ecol%C3%B3gico+manual PDF link annotation
    • http://bowlinggreenhsclassof66.com/clients/b/bd/bdf8ab256cd88a603fc2b95a051c5839/File/68773093351.pdfIn PDF document text
    • http://hgbs.de/userfiles/file/30768025490.pdfIn PDF document text
    • http://www.uvhk.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608b71046ed41---zolozi.pdfIn PDF document text
    • https://www.azembay.com/wp-content/plugins/super-forms/uploads/php/files/2re461os9j1og6he350cgo8km6/ruwikejazukagawajapuno.pdfIn PDF document text
    • https://systematix.pl/userfiles/file/68989897053.pdfIn PDF document text
    • http://xn----8sbemnkjd7bfu.xn--p1ai/design/img/upload/file/78393097195.pdfIn PDF document text
    • https://kolodezrus.ru/wp-content/plugins/super-forms/uploads/php/files/f5c60760a365d23789dab11cb7598f07/964591470.pdfIn PDF document text
    • https://www.andimoda.com/wp-content/plugins/super-forms/uploads/php/files/76bbd2b66bed76224c07a6a097a99004/felitibiwafew.pdfIn PDF document text
    • https://mojer.bg/files/53410308008.pdfIn PDF document text
    • http://robertsrucker.com/clients/7/7f/7f5ecd1287ec2152c36a7dc1808edcbf/File/zogopubagumerijo.pdfIn PDF document text
    • http://sanchariglobal.com/userfiles/file/vovaxinun.pdfIn PDF document text
    • http://hitecds.com/userfiles/file/bifoxusisabupokunofeko.pdfIn PDF document text
    • https://www.ideaklinikbursa.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ca0275a782---tigepiximigijakolexovogaz.pdfIn PDF document text
    • http://fioredda.com/userfiles/files/kupejefujeru.pdfIn PDF document text
    • http://ikra-ekb.ru/files/fckeditor/file/nudajomalutit.pdfIn PDF document text
    • https://indacphuc.com/wp-content/plugins/super-forms/uploads/php/files/kdughv3r2reb774ulripne9pkk/salojibe.pdfIn PDF document text
    • https://n-v-v.dk/userfiles/file/gejor.pdfIn PDF document text
    • http://soles2walk.cz/data/file/61470888827.pdfIn PDF document text
    • https://www.reliancecareuk.com/wp-content/plugins/super-forms/uploads/php/files/e1b3f69ec6601dfb7d3403449b5f21a9/35234951938.pdfIn PDF document text
    • http://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c1a8b135e0c---jofivuweri.pdfIn PDF document text
    • http://radio-salsa.com/php/rs/filesupload/file/59452827211.pdfIn PDF document text
    • http://www.nisbd.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077b6a50df83---44472371850.pdfIn PDF document text
    • https://janeunchained.com/wp-content/plugins/super-forms/uploads/php/files/768ttn3tqc6fq1ui1ei2muqe8f/36267340509.pdfIn PDF document text
    • https://plumcourse.com/wp-content/plugins/super-forms/uploads/php/files/9c8783ff488bff5f1f0c4770ae0d9668/newenamonuwitixovasoke.pdfIn PDF document text
    • http://www.agenbenangbandung.net/file/nexadunavadorogiteg.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_off00010007.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10007 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00011819.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11819 19576 bytes
SHA-256: e222cadc67a7ec9668c36c25730b4d639d0de31e27d9fa9eb0f8c124374f7682
font_02_sfnt_off00014855.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14855 10944 bytes
SHA-256: 15eafb540e06574222119edc4e2da16fa6d29374fde223fa2ffa507615bc09a7