Malicious PDF — malware analysis report

Static analysis result for SHA-256 87e26d8c4c380461…

MALICIOUS

PDF

86.3 KB Created: 2021-09-24 12:11:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 5ffaaa4e4742d0d28ab9b1f4ed4211f6 SHA-1: 8ce5c500a4784d27bda7a65191420da375f5ecc1 SHA-256: 87e26d8c4c380461954075dfa20f993432e408572997095685fa12494d8b52d9
96 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many pointing to compromised WordPress sites and disposable domains, indicating a link farm or redirection scheme. The ML classifier strongly flagged this PDF as malicious, and heuristics confirm it's a link farm on disposable hosting. The primary purpose appears to be directing users to external, potentially malicious, content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://inwebjor.ru/uplcv?utm_term=the+new+mutants+online+watch PDF link annotation
    • https://www.ediliziaindustriale.com/wp-content/plugins/formcraft/file-upload/server/content/files/16145af860afda---8881256610.pdfIn PDF document text
    • https://copperscrap.wasteequipment.net/ckfinder/userfiles/files/pepunixizugazixewasunas.pdfIn PDF document text
    • http://clear-es.net/yamituki-n/uploads/files/jinoridozojesevituko.pdfIn PDF document text
    • http://kitpaisal.com/mypicture/file/94167565072.pdfIn PDF document text
    • https://camping-du-lac-dijon.com/userfiles/fichiers/wawusedadorajumamib.pdfIn PDF document text
    • http://muacuoi.vn/Pictures/files/wakolumod.pdfIn PDF document text
    • http://www.corazondelsol.es/ckfinder/userfiles/files/43069990015.pdfIn PDF document text
    • https://ever-progress.com/upload/files/melemujika.pdfIn PDF document text
    • https://sunsoftinfoway.net/ckfinder/userfiles/files/zebivedomazunabumeza.pdfIn PDF document text
    • http://archidaldegan.eu/userfiles/files/zunigasutaviduwalatil.pdfIn PDF document text
    • https://lescourailleurs.com/upload/editor/file/nopatogaxenufibukajidi.pdfIn PDF document text
    • http://fortlauderdalelimorental.net/wp-content/plugins/formcraft/file-upload/server/content/files/1614b2fd922b32---35519169125.pdfIn PDF document text
    • http://hillsdalehorseboarding.com/ckfinder/userfiles/files/8564514049.pdfIn PDF document text
    • https://www.scanworld.se/wp-content/plugins/formcraft/file-upload/server/content/files/16131cf55024e0---88364612738.pdfIn PDF document text
    • https://jagamimpi.com/contents/files/fidekakuzebagito.pdfIn PDF document text
    • https://speedwayinfo.hu/uploads/file/80007296955.pdfIn PDF document text
    • https://gangnampools.com/contents/files/disegikuvaver.pdfIn PDF document text
    • http://gysanya.com/upload/file/21090421092267838544gzok4417y4.pdfIn PDF document text
    • https://2winit.com/Files/files/xodikotufomozijamokakodox.pdfIn PDF document text
    • http://lamexmarket.com/uploads/files/xifomuzipekij.pdfIn PDF document text
    • http://www.1atlanticfunding.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132189ec0ffb---95496218900.pdfIn PDF document text
    • http://www.chinahkcarplate.com/wp-content/plugins/formcraft/file-upload/server/content/files/161358131629c0---dokexoxuvurifat.pdfIn PDF document text
    • http://kerekagy.hu/UserFiles/file/wotizokuganupufanabaropax.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_off0000ed7e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED7E 17544 bytes
SHA-256: 4e8cb5315c0a268a63501569ba251b1d7fc729426a0dccb8100877b5dc41cfa7
font_01_sfnt_off00011b95.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B95 10544 bytes
SHA-256: 7d0c15b767376837d84ab433619b88d1dc05fde6897af7870c60d2a8eabb14ce
font_02_sfnt_off00013383.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13383 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1