Malicious PDF — malware analysis report

Static analysis result for SHA-256 106617198d791992…

MALICIOUS

PDF

87.4 KB Created: 2021-07-16 01:11:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 1be9f2eb2e525aa3d902e93276b2bcf0 SHA-1: 31068ba318c6df4bd308384c6f35d1a196de875c SHA-256: 106617198d79199233bddd44ee20e7d788666c916ed14dfcb0bc8c71d027d456
96 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs, many of which point to compromised WordPress sites and are structured as a link farm. The ML classifier strongly indicated maliciousness, and the heuristic firings confirm the presence of external URIs and a link farm on disposable hosting. No scripts were extracted, but the primary attack pattern involves directing users to potentially malicious external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

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://synerhu.ru/uplcv?utm_term=how+do+you+collate+pdf+files PDF link annotation
    • https://www.adelaarenergy.com/wp-content/plugins/super-forms/uploads/php/files/3mnjfc0ilvuq1bhs8usa6hu1jn/81485741764.pdfIn PDF document text
    • http://counterreaction.net/wp-content/plugins/formcraft/file-upload/server/content/files/1607fabf28957d---tofugebategaj.pdfIn PDF document text
    • https://bosingels.nl/ckfinder/userfiles/files/rivijuvuja.pdfIn PDF document text
    • http://www.toeterloeh44.de/files/zufuraf.pdfIn PDF document text
    • http://hillcresthigh1971.com/clients/9/9f/9fbf9047a6869172a982db6f42f05a9a/File/21462333504.pdfIn PDF document text
    • https://iamluno.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b15a234a607---situsunofatuzuj.pdfIn PDF document text
    • https://metricgroup.it/uploads/file/pikomeduvilozetutiz.pdfIn PDF document text
    • https://sf-tfi-pgu.uz/wp-content/plugins/super-forms/uploads/php/files/b6ae07627a2ee3a0ab924d9b41e782b1/25604660986.pdfIn PDF document text
    • http://sunnysolutions.it/uploads/assets/file/78055602506.pdfIn PDF document text
    • https://n-zvuk.ru/upload/file/gazokitulinopolagekav.pdfIn PDF document text
    • https://ajur.rest/uploads/userfiles/file/34698921864.pdfIn PDF document text
    • http://andreevmag.com/wp-content/plugins/super-forms/uploads/php/files/af116cd12c602fcc70c25f52fa6b479b/tavetatogulosad.pdfIn PDF document text
    • https://gk-termopanel.ru/wp-content/plugins/super-forms/uploads/php/files/d50f14538582206f5de7514abd4904ad/sekidobimuniferusikek.pdfIn PDF document text
    • http://ophirtonhotel.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160850dec32ec1---95743878382.pdfIn PDF document text
    • http://buddhavehicle.com/userfiles/file/30838240100.pdfIn PDF document text
    • http://itaindustrial.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607fea102806f---77162831005.pdfIn PDF document text
    • http://multiseal.com.ph/wp-content/plugins/formcraft/file-upload/server/content/files/1609efbfc4528c---79346608349.pdfIn PDF document text
    • http://mp-hd.de/data/aktualnosci_imgs/file/gixapufepebuzip.pdfIn PDF document text
    • https://hram-uspeniya.ru/ckfinder/userfiles/files/77706219420.pdfIn PDF document text
    • http://dinskayarealty.ru/media/file/68119569080.pdfIn PDF document text
    • https://lerong.vn/wp-content/plugins/super-forms/uploads/php/files/a2e8b65003b1f62935a4552239663c2c/jibutepiwabegitopinavom.pdfIn PDF document text
    • http://sieuthibongda.net/ckfinder/userfiles/files/nufadozifanosomenakexon.pdfIn PDF document text
    • https://myphi.biz/nbloom/fckuploads/file/10728021509.pdfIn PDF document text
    • http://fcv-bo.org/data/fcv-bo/userfiles/file/7733924947.pdfIn PDF document text
    • http://kaplanpm.com/wp-content/plugins/formcraft/file-upload/server/content/files/160856a0d11519---fevafonekagunojutifoje.pdfIn PDF document text
    • http://big-blue-bus.com/pics/fotos/1/file/15771812159.pdfIn PDF document text
    • https://chefinhogourmet.com/wp-content/plugins/super-forms/uploads/php/files/98cf73f584b32abac31a91d78d5d447f/tebulunonupogut.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_off0000f127.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF127 10700 bytes
SHA-256: 473e32af93014c1743dfe9466245bd7e30ae616a90e441afcad9d8797af9109e
font_01_sfnt_off000109e2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109E2 17056 bytes
SHA-256: 982aeadac0481f6ed8d7d83012a1ee565b633c9dded6eb8dca21d392ef9250df
font_02_sfnt_off0001367e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1367E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1